diff --git a/docs/schema-postgres.sql b/docs/schema-postgres.sql
index f81b44a..76fab83 100644
--- a/docs/schema-postgres.sql
+++ b/docs/schema-postgres.sql
@@ -1,8 +1,4 @@
--- PostgreSQL version of schema-mariadb.sql
 
--- PostgreSQL 里通常先手动创建数据库，再连接进去执行下面脚本：
--- CREATE DATABASE kepan;
--- \c kepan
 
 -- =========================
 -- Enum types
@@ -30,11 +26,53 @@ BEGIN
     END IF;
 
     IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'upload_part_status_enum') THEN
-        CREATE TYPE upload_part_status_enum AS ENUM ('pending', 'uploaded');
+        CREATE TYPE upload_part_status_enum AS ENUM ('pending', 'uploaded', 'failed');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'user_status_enum') THEN
+        CREATE TYPE user_status_enum AS ENUM ('pending_verification', 'active', 'locked', 'disabled');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'folder_type_enum') THEN
+        CREATE TYPE folder_type_enum AS ENUM ('normal', 'root', 'system');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'share_status_enum') THEN
+        CREATE TYPE share_status_enum AS ENUM ('active', 'expired', 'revoked', 'deleted');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'share_member_status_enum') THEN
+        CREATE TYPE share_member_status_enum AS ENUM ('pending', 'accepted', 'rejected', 'revoked');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'favorite_item_type_enum') THEN
+        CREATE TYPE favorite_item_type_enum AS ENUM ('file', 'folder');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'view_mode_enum') THEN
+        CREATE TYPE view_mode_enum AS ENUM ('list', 'grid');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'sort_by_enum') THEN
+        CREATE TYPE sort_by_enum AS ENUM ('name', 'size', 'created_at', 'updated_at', 'last_accessed_at');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'sort_direction_enum') THEN
+        CREATE TYPE sort_direction_enum AS ENUM ('asc', 'desc');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'preview_status_enum') THEN
+        CREATE TYPE preview_status_enum AS ENUM ('pending', 'ready', 'failed');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'scan_result_enum') THEN
+        CREATE TYPE scan_result_enum AS ENUM ('pending', 'clean', 'infected', 'blocked', 'failed');
     END IF;
 END
 $$;
 
+CREATE EXTENSION IF NOT EXISTS pg_trgm;
+
 -- =========================
 -- updated_at trigger
 -- =========================
@@ -55,14 +93,25 @@ CREATE TABLE IF NOT EXISTS "user" (
     email VARCHAR(255) NOT NULL,
     password_hash VARCHAR(255) NOT NULL,
     role VARCHAR(50) NOT NULL DEFAULT 'USER',
+    status user_status_enum NOT NULL DEFAULT 'active',
+    email_verified BOOLEAN NOT NULL DEFAULT FALSE,
+    email_verified_at TIMESTAMP NULL,
     storage_limit BIGINT NOT NULL DEFAULT 10737418240,
     storage_used BIGINT NOT NULL DEFAULT 0,
+    last_login_at TIMESTAMP NULL,
+    failed_login_count INTEGER NOT NULL DEFAULT 0,
+    locked_until TIMESTAMP NULL,
+    password_changed_at TIMESTAMP NULL,
+    deleted_at TIMESTAMP NULL,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
-    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
-    CONSTRAINT uk_username UNIQUE (username),
-    CONSTRAINT uk_email UNIQUE (email)
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
 );
 
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_username_ci ON "user" ((LOWER(username)));
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_email_ci ON "user" ((LOWER(email)));
+CREATE INDEX IF NOT EXISTS idx_user_status ON "user" (status);
+CREATE INDEX IF NOT EXISTS idx_user_locked_until ON "user" (locked_until);
+
 CREATE TRIGGER trg_user_updated_at
 BEFORE UPDATE ON "user"
 FOR EACH ROW
@@ -92,7 +141,8 @@ CREATE TABLE IF NOT EXISTS user_group_member (
 -- =========================
 CREATE TABLE IF NOT EXISTS storage_object (
     object_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
-    object_hash CHAR(64) NOT NULL,
+    object_hash CHAR(64),
+    hash_algorithm VARCHAR(32) NOT NULL DEFAULT 'sha256',
     bucket_name VARCHAR(100) NOT NULL,
     object_key VARCHAR(1024) NOT NULL,
     object_size BIGINT NOT NULL,
@@ -101,14 +151,25 @@ CREATE TABLE IF NOT EXISTS storage_object (
     content_type VARCHAR(255),
     storage_class VARCHAR(50),
     upload_status upload_status_enum NOT NULL DEFAULT 'active',
+    scan_status scan_result_enum NOT NULL DEFAULT 'pending',
+    moderation_status VARCHAR(32) NOT NULL DEFAULT 'pending',
+    quarantined_at TIMESTAMP NULL,
+    last_scanned_at TIMESTAMP NULL,
+    metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
     ref_count INTEGER NOT NULL DEFAULT 1,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     deleted_at TIMESTAMP NULL,
-    CONSTRAINT uk_object_hash UNIQUE (object_hash),
     CONSTRAINT uk_bucket_object_key UNIQUE (bucket_name, object_key)
 );
 
+CREATE UNIQUE INDEX IF NOT EXISTS uk_storage_object_hash_algo_size
+    ON storage_object (hash_algorithm, object_hash, object_size)
+    WHERE object_hash IS NOT NULL;
+
+CREATE INDEX IF NOT EXISTS idx_storage_object_scan_status ON storage_object (scan_status);
+CREATE INDEX IF NOT EXISTS idx_storage_object_moderation_status ON storage_object (moderation_status);
+
 CREATE INDEX IF NOT EXISTS idx_storage_object_upload_status
 ON storage_object(upload_status);
 
@@ -125,16 +186,30 @@ CREATE TABLE IF NOT EXISTS folder (
     owner_id BIGINT NOT NULL,
     parent_folder_id BIGINT NULL,
     folder_name VARCHAR(255) NOT NULL,
-    size BIGINT NOT NULL DEFAULT 0,
+    cached_size BIGINT NOT NULL DEFAULT 0,
     status folder_status_enum NOT NULL DEFAULT 'active',
+    folder_type folder_type_enum NOT NULL DEFAULT 'normal',
+    deleted_by BIGINT NULL,
+    restored_at TIMESTAMP NULL,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     deleted_at TIMESTAMP NULL,
     CONSTRAINT fk_folder_owner FOREIGN KEY (owner_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
     CONSTRAINT fk_folder_parent FOREIGN KEY (parent_folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
-    CONSTRAINT uk_folder_name_in_parent UNIQUE (parent_folder_id, folder_name, owner_id, status)
+    CONSTRAINT fk_folder_deleted_by FOREIGN KEY (deleted_by) REFERENCES "user"(user_id) ON DELETE SET NULL
 );
 
+CREATE UNIQUE INDEX IF NOT EXISTS uk_folder_root_name_active
+    ON folder (owner_id, folder_name)
+    WHERE parent_folder_id IS NULL AND status = 'active';
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_folder_child_name_active
+    ON folder (owner_id, parent_folder_id, folder_name)
+    WHERE parent_folder_id IS NOT NULL AND status = 'active';
+
+CREATE INDEX IF NOT EXISTS idx_folder_owner_parent_status ON folder (owner_id, parent_folder_id, status);
+CREATE INDEX IF NOT EXISTS idx_folder_name_trgm ON folder USING gin ((LOWER(folder_name)) gin_trgm_ops);
+
 CREATE TRIGGER trg_folder_updated_at
 BEFORE UPDATE ON folder
 FOR EACH ROW
@@ -155,6 +230,9 @@ CREATE TABLE IF NOT EXISTS "file" (
     file_size BIGINT NOT NULL,
     is_latest BOOLEAN NOT NULL DEFAULT TRUE,
     status file_status_enum NOT NULL DEFAULT 'active',
+    deleted_by BIGINT NULL,
+    restored_at TIMESTAMP NULL,
+    last_accessed_at TIMESTAMP NULL,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     deleted_at TIMESTAMP NULL,
@@ -162,9 +240,16 @@ CREATE TABLE IF NOT EXISTS "file" (
     CONSTRAINT fk_file_owner FOREIGN KEY (owner_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
     CONSTRAINT fk_file_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
     CONSTRAINT fk_file_storage_object FOREIGN KEY (storage_object_id) REFERENCES storage_object(object_id),
-    CONSTRAINT uk_file_name_in_folder UNIQUE (folder_id, file_name, owner_id, status)
+    CONSTRAINT fk_file_deleted_by FOREIGN KEY (deleted_by) REFERENCES "user"(user_id) ON DELETE SET NULL
 );
 
+CREATE UNIQUE INDEX IF NOT EXISTS uk_file_name_active_in_folder
+    ON "file" (owner_id, folder_id, file_name)
+    WHERE status = 'active';
+
+CREATE INDEX IF NOT EXISTS idx_file_last_accessed_at ON "file" (last_accessed_at);
+CREATE INDEX IF NOT EXISTS idx_file_name_trgm ON "file" USING gin ((LOWER(file_name)) gin_trgm_ops);
+
 CREATE INDEX IF NOT EXISTS idx_file_storage_object_id
 ON "file"(storage_object_id);
 
@@ -186,17 +271,45 @@ CREATE TABLE IF NOT EXISTS acl (
     user_id BIGINT NULL,
     group_id BIGINT NULL,
     permission VARCHAR(100) NOT NULL,
+    permission_role VARCHAR(50) NOT NULL DEFAULT 'viewer',
+    can_preview BOOLEAN NOT NULL DEFAULT TRUE,
+    can_download BOOLEAN NOT NULL DEFAULT TRUE,
+    can_save BOOLEAN NOT NULL DEFAULT FALSE,
+    can_share BOOLEAN NOT NULL DEFAULT FALSE,
+    expire_at TIMESTAMP NULL,
+    granted_by BIGINT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     CONSTRAINT fk_acl_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE CASCADE,
     CONSTRAINT fk_acl_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
     CONSTRAINT fk_acl_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
     CONSTRAINT fk_acl_group FOREIGN KEY (group_id) REFERENCES user_group(id) ON DELETE CASCADE,
-    CONSTRAINT chk_acl_target CHECK (
-        (user_id IS NOT NULL OR group_id IS NOT NULL)
-        AND
-        (file_id IS NOT NULL OR folder_id IS NOT NULL)
-    )
+    CONSTRAINT fk_acl_granted_by FOREIGN KEY (granted_by) REFERENCES "user"(user_id) ON DELETE SET NULL,
+    CONSTRAINT chk_acl_subject_exactly_one CHECK (num_nonnulls(user_id, group_id) = 1),
+    CONSTRAINT chk_acl_resource_exactly_one CHECK (num_nonnulls(file_id, folder_id) = 1)
 );
 
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_file_user
+    ON acl (file_id, user_id)
+    WHERE file_id IS NOT NULL AND user_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_file_group
+    ON acl (file_id, group_id)
+    WHERE file_id IS NOT NULL AND group_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_folder_user
+    ON acl (folder_id, user_id)
+    WHERE folder_id IS NOT NULL AND user_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_folder_group
+    ON acl (folder_id, group_id)
+    WHERE folder_id IS NOT NULL AND group_id IS NOT NULL;
+
+CREATE TRIGGER trg_acl_updated_at
+BEFORE UPDATE ON acl
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
 -- =========================
 -- 分享表
 -- =========================
@@ -207,47 +320,99 @@ CREATE TABLE IF NOT EXISTS share (
     file_id BIGINT NULL,
     folder_id BIGINT NULL,
     share_link VARCHAR(255) NOT NULL UNIQUE,
+    share_code VARCHAR(64) NOT NULL,
+    status share_status_enum NOT NULL DEFAULT 'active',
     share_type VARCHAR(50) NOT NULL DEFAULT 'public',
+    permission_role VARCHAR(50) NOT NULL DEFAULT 'viewer',
+    allow_preview BOOLEAN NOT NULL DEFAULT TRUE,
+    allow_download BOOLEAN NOT NULL DEFAULT TRUE,
+    allow_save BOOLEAN NOT NULL DEFAULT FALSE,
+    allow_reshare BOOLEAN NOT NULL DEFAULT FALSE,
+    require_login BOOLEAN NOT NULL DEFAULT FALSE,
+    max_visits INTEGER NULL,
+    max_downloads INTEGER NULL,
     password_hash VARCHAR(255),
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    last_accessed_at TIMESTAMP NULL,
     expire_time TIMESTAMP NULL,
     visit_count INTEGER NOT NULL DEFAULT 0,
     download_count INTEGER NOT NULL DEFAULT 0,
     CONSTRAINT fk_share_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
     CONSTRAINT fk_share_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE CASCADE,
     CONSTRAINT fk_share_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
-    CONSTRAINT chk_share_target CHECK (
-        (file_id IS NOT NULL AND folder_id IS NULL)
-        OR
-        (file_id IS NULL AND folder_id IS NOT NULL)
+    CONSTRAINT chk_share_target CHECK (num_nonnulls(file_id, folder_id) = 1),
+    CONSTRAINT chk_share_limits CHECK (
+        (max_visits IS NULL OR max_visits >= 0)
+        AND
+        (max_downloads IS NULL OR max_downloads >= 0)
     )
 );
 
+CREATE UNIQUE INDEX IF NOT EXISTS uk_share_code ON share (share_code);
+CREATE INDEX IF NOT EXISTS idx_share_user_status ON share (user_id, status);
+CREATE INDEX IF NOT EXISTS idx_share_expire_time ON share (expire_time);
+
+CREATE TRIGGER trg_share_updated_at
+BEFORE UPDATE ON share
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
 -- =========================
 -- 日志表
 -- =========================
 CREATE TABLE IF NOT EXISTS "log" (
-    id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
-    user_id BIGINT NOT NULL,
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NULL,
+    actor_type VARCHAR(50) NOT NULL DEFAULT 'user',
     operation VARCHAR(255) NOT NULL,
+    target_type VARCHAR(50) NULL,
+    target_id BIGINT NULL,
+    result VARCHAR(20) NOT NULL DEFAULT 'success',
+    request_id VARCHAR(128) NULL,
+    user_agent VARCHAR(255) NULL,
+    metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
     details TEXT,
     ip_address VARCHAR(45),
     performed_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
-    CONSTRAINT fk_log_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+    CONSTRAINT fk_log_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE SET NULL
 );
 
+CREATE INDEX IF NOT EXISTS idx_log_performed_at ON "log" (performed_at);
+CREATE INDEX IF NOT EXISTS idx_log_user_operation ON "log" (user_id, operation);
+CREATE INDEX IF NOT EXISTS idx_log_target ON "log" (target_type, target_id);
+CREATE INDEX IF NOT EXISTS idx_log_request_id ON "log" (request_id);
+
 -- =========================
 -- 通知表
 -- =========================
 CREATE TABLE IF NOT EXISTS notification (
-    id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     user_id BIGINT NOT NULL,
-    message VARCHAR(255) NOT NULL,
+    title VARCHAR(255) NULL,
+    type VARCHAR(50) NOT NULL DEFAULT 'system',
+    channel VARCHAR(50) NOT NULL DEFAULT 'in_app',
+    message TEXT NOT NULL,
+    payload JSONB NOT NULL DEFAULT '{}'::jsonb,
+    sent_at TIMESTAMP NULL,
     is_read BOOLEAN DEFAULT FALSE,
+    read_at TIMESTAMP NULL,
+    status VARCHAR(50) NOT NULL DEFAULT 'pending',
+    sender_user_id BIGINT NULL,
     created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
-    CONSTRAINT fk_notification_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_notification_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_notification_sender_user FOREIGN KEY (sender_user_id) REFERENCES "user"(user_id) ON DELETE SET NULL
 );
 
+CREATE INDEX IF NOT EXISTS idx_notification_user_status ON notification (user_id, status, is_read);
+CREATE INDEX IF NOT EXISTS idx_notification_created_at ON notification (created_at);
+
+CREATE TRIGGER trg_notification_updated_at
+BEFORE UPDATE ON notification
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
 -- =========================
 -- 视图 v_file_folder_details
 -- =========================
@@ -272,7 +437,7 @@ SELECT
     'folder' AS item_type,
     fo.folder_id AS id,
     fo.folder_name AS name,
-    fo.size,
+    fo.cached_size AS size,
     'inode/directory' AS mime_type,
     fo.parent_folder_id AS parent_id,
     fo.owner_id AS owner_id,
@@ -403,7 +568,7 @@ SELECT
     'folder' AS item_type,
     fo.folder_id AS id,
     fo.folder_name AS name,
-    fo.size,
+    fo.cached_size AS size,
     fo.parent_folder_id AS parent_id,
     fo.owner_id AS owner_id,
     u.username AS owner_name,
@@ -418,23 +583,38 @@ WHERE fo.status = 'deleted' AND fo.deleted_at IS NOT NULL;
 CREATE TABLE IF NOT EXISTS upload_task (
     task_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
     user_id BIGINT NOT NULL,
+    folder_id BIGINT NULL,
+    file_name VARCHAR(255) NULL,
+    mime_type VARCHAR(255) NULL,
     bucket_name VARCHAR(100) NOT NULL,
     object_key VARCHAR(1024) NOT NULL,
     object_hash CHAR(64),
     total_size BIGINT NOT NULL,
+    chunk_size BIGINT NULL,
+    uploaded_bytes BIGINT NOT NULL DEFAULT 0,
+    client_file_id VARCHAR(255) NULL,
     upload_id VARCHAR(255),
     upload_mode upload_mode_enum NOT NULL DEFAULT 'single',
     status upload_task_status_enum NOT NULL DEFAULT 'init',
+    last_error TEXT NULL,
+    completed_at TIMESTAMP NULL,
     expired_at TIMESTAMP NULL,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     CONSTRAINT fk_upload_task_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_upload_task_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE SET NULL,
     CONSTRAINT uk_upload_target UNIQUE (bucket_name, object_key, upload_id)
 );
 
 CREATE INDEX IF NOT EXISTS idx_upload_task_user_status
 ON upload_task(user_id, status);
 
+CREATE INDEX IF NOT EXISTS idx_upload_task_expired_at ON upload_task (expired_at);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_upload_task_user_client_file_id
+    ON upload_task (user_id, client_file_id)
+    WHERE client_file_id IS NOT NULL;
+
 CREATE TRIGGER trg_upload_task_updated_at
 BEFORE UPDATE ON upload_task
 FOR EACH ROW
@@ -450,13 +630,995 @@ CREATE TABLE IF NOT EXISTS upload_task_part (
     etag VARCHAR(128),
     part_size BIGINT NOT NULL,
     status upload_part_status_enum NOT NULL DEFAULT 'pending',
+    checksum CHAR(64) NULL,
+    uploaded_at TIMESTAMP NULL,
+    retry_count INTEGER NOT NULL DEFAULT 0,
     created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
     CONSTRAINT fk_upload_task_part_task FOREIGN KEY (task_id) REFERENCES upload_task(task_id) ON DELETE CASCADE,
     CONSTRAINT uk_task_part UNIQUE (task_id, part_number)
 );
 
+CREATE INDEX IF NOT EXISTS idx_upload_task_part_task_status ON upload_task_part (task_id, status);
+
 CREATE TRIGGER trg_upload_task_part_updated_at
 BEFORE UPDATE ON upload_task_part
 FOR EACH ROW
-EXECUTE FUNCTION set_updated_at();
\ No newline at end of file
+EXECUTE FUNCTION set_updated_at();
+
+-- =========================
+-- 2) 新增表
+-- =========================
+
+-- 密码找回 token
+CREATE TABLE IF NOT EXISTS password_reset_token (
+    token_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    token_hash CHAR(64) NOT NULL UNIQUE,
+    expire_at TIMESTAMP NOT NULL,
+    used_at TIMESTAMP NULL,
+    requester_ip VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_password_reset_token_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_password_reset_token_user_expire
+    ON password_reset_token (user_id, expire_at);
+
+-- 邮箱验证 token
+CREATE TABLE IF NOT EXISTS email_verification_token (
+    token_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    token_hash CHAR(64) NOT NULL UNIQUE,
+    expire_at TIMESTAMP NOT NULL,
+    verified_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_email_verification_token_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_email_verification_token_user_expire
+    ON email_verification_token (user_id, expire_at);
+
+-- 会话表 / refresh token
+CREATE TABLE IF NOT EXISTS user_session (
+    session_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    refresh_token_hash CHAR(64) NOT NULL UNIQUE,
+    client_type VARCHAR(50) NOT NULL DEFAULT 'web',
+    device_id VARCHAR(255) NULL,
+    device_name VARCHAR(255) NULL,
+    ip_address VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    last_seen_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    expire_at TIMESTAMP NOT NULL,
+    revoked_at TIMESTAMP NULL,
+    CONSTRAINT fk_user_session_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_user_session_user_expire
+    ON user_session (user_id, expire_at);
+
+-- 分享成员：支撑“分享给别人”和“接受他人分享”
+CREATE TABLE IF NOT EXISTS share_member (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    share_id BIGINT NOT NULL,
+    user_id BIGINT NULL,
+    group_id BIGINT NULL,
+    status share_member_status_enum NOT NULL DEFAULT 'pending',
+    target_folder_id BIGINT NULL,
+    accepted_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_share_member_share FOREIGN KEY (share_id) REFERENCES share(share_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_member_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_member_group FOREIGN KEY (group_id) REFERENCES user_group(id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_member_target_folder FOREIGN KEY (target_folder_id) REFERENCES folder(folder_id) ON DELETE SET NULL,
+    CONSTRAINT chk_share_member_subject_exactly_one CHECK (num_nonnulls(user_id, group_id) = 1)
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_share_member_user
+    ON share_member (share_id, user_id)
+    WHERE user_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_share_member_group
+    ON share_member (share_id, group_id)
+    WHERE group_id IS NOT NULL;
+
+CREATE INDEX IF NOT EXISTS idx_share_member_share_status ON share_member (share_id, status);
+
+DROP TRIGGER IF EXISTS trg_share_member_updated_at ON share_member;
+CREATE TRIGGER trg_share_member_updated_at
+BEFORE UPDATE ON share_member
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+-- 星标：文件、文件夹都可加星
+CREATE TABLE IF NOT EXISTS favorite_item (
+    favorite_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    item_type favorite_item_type_enum NOT NULL,
+    file_id BIGINT NULL,
+    folder_id BIGINT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_favorite_item_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_favorite_item_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE CASCADE,
+    CONSTRAINT fk_favorite_item_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
+    CONSTRAINT chk_favorite_item_target_exactly_one CHECK (num_nonnulls(file_id, folder_id) = 1),
+    CONSTRAINT chk_favorite_item_type_match CHECK (
+        (item_type = 'file' AND file_id IS NOT NULL AND folder_id IS NULL)
+        OR
+        (item_type = 'folder' AND folder_id IS NOT NULL AND file_id IS NULL)
+    )
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_favorite_item_file
+    ON favorite_item (user_id, file_id)
+    WHERE file_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_favorite_item_folder
+    ON favorite_item (user_id, folder_id)
+    WHERE folder_id IS NOT NULL;
+
+-- 目录视图偏好：全局默认 + 每个目录覆盖
+CREATE TABLE IF NOT EXISTS user_folder_preference (
+    preference_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    folder_id BIGINT NULL,
+    view_mode view_mode_enum NOT NULL DEFAULT 'list',
+    sort_by sort_by_enum NOT NULL DEFAULT 'name',
+    sort_direction sort_direction_enum NOT NULL DEFAULT 'asc',
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_user_folder_preference_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_user_folder_preference_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_folder_preference_default
+    ON user_folder_preference (user_id)
+    WHERE folder_id IS NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_folder_preference_folder
+    ON user_folder_preference (user_id, folder_id)
+    WHERE folder_id IS NOT NULL;
+
+DROP TRIGGER IF EXISTS trg_user_folder_preference_updated_at ON user_folder_preference;
+CREATE TRIGGER trg_user_folder_preference_updated_at
+BEFORE UPDATE ON user_folder_preference
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+-- 预览产物：图片缩略图、PDF 页图、视频预览等
+CREATE TABLE IF NOT EXISTS file_preview_asset (
+    preview_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    source_object_id BIGINT NOT NULL,
+    preview_object_id BIGINT NULL,
+    preview_type VARCHAR(50) NOT NULL,
+    page_no INTEGER NULL,
+    mime_type VARCHAR(255) NULL,
+    width INTEGER NULL,
+    height INTEGER NULL,
+    duration_ms BIGINT NULL,
+    status preview_status_enum NOT NULL DEFAULT 'pending',
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_file_preview_asset_source_object FOREIGN KEY (source_object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE,
+    CONSTRAINT fk_file_preview_asset_preview_object FOREIGN KEY (preview_object_id) REFERENCES storage_object(object_id) ON DELETE SET NULL
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_file_preview_asset_type_page
+    ON file_preview_asset (source_object_id, preview_type, (COALESCE(page_no, -1)));
+
+DROP TRIGGER IF EXISTS trg_file_preview_asset_updated_at ON file_preview_asset;
+CREATE TRIGGER trg_file_preview_asset_updated_at
+BEFORE UPDATE ON file_preview_asset
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+-- 媒体元数据：预览 / 转码 / 播放所需
+CREATE TABLE IF NOT EXISTS file_media_metadata (
+    metadata_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    source_object_id BIGINT NOT NULL UNIQUE,
+    width INTEGER NULL,
+    height INTEGER NULL,
+    duration_ms BIGINT NULL,
+    page_count INTEGER NULL,
+    bitrate INTEGER NULL,
+    sample_rate INTEGER NULL,
+    video_codec VARCHAR(64) NULL,
+    audio_codec VARCHAR(64) NULL,
+    extra_metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
+    extracted_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_file_media_metadata_source_object FOREIGN KEY (source_object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE
+);
+
+-- 扫描结果：病毒 / 色情 / 其他违规检测
+CREATE TABLE IF NOT EXISTS object_scan_result (
+    scan_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    object_id BIGINT NOT NULL,
+    scan_type VARCHAR(50) NOT NULL,
+    engine_name VARCHAR(100) NULL,
+    engine_version VARCHAR(100) NULL,
+    result scan_result_enum NOT NULL DEFAULT 'pending',
+    details JSONB NOT NULL DEFAULT '{}'::jsonb,
+    scanned_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_object_scan_result_object FOREIGN KEY (object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_object_scan_result_object_scanned_at
+    ON object_scan_result (object_id, scanned_at DESC);
+
+-- 违规处理工单
+CREATE TABLE IF NOT EXISTS moderation_case (
+    case_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    object_id BIGINT NOT NULL,
+    file_id BIGINT NULL,
+    reason_type VARCHAR(50) NOT NULL,
+    confidence NUMERIC(5,4) NULL,
+    status VARCHAR(50) NOT NULL DEFAULT 'pending',
+    resolution VARCHAR(50) NULL,
+    detail JSONB NOT NULL DEFAULT '{}'::jsonb,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    handled_by BIGINT NULL,
+    handled_at TIMESTAMP NULL,
+    CONSTRAINT fk_moderation_case_object FOREIGN KEY (object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE,
+    CONSTRAINT fk_moderation_case_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE SET NULL,
+    CONSTRAINT fk_moderation_case_handled_by FOREIGN KEY (handled_by) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_moderation_case_status_created_at
+    ON moderation_case (status, created_at DESC);
+
+DROP TRIGGER IF EXISTS trg_moderation_case_updated_at ON moderation_case;
+CREATE TRIGGER trg_moderation_case_updated_at
+BEFORE UPDATE ON moderation_case
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+-- 安全事件：限制滥用、审计风险行为
+CREATE TABLE IF NOT EXISTS security_event (
+    event_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NULL,
+    session_id BIGINT NULL,
+    event_type VARCHAR(50) NOT NULL,
+    severity VARCHAR(20) NOT NULL DEFAULT 'info',
+    target_type VARCHAR(50) NULL,
+    target_id BIGINT NULL,
+    ip_address VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    detail JSONB NOT NULL DEFAULT '{}'::jsonb,
+    occurred_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_security_event_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE SET NULL,
+    CONSTRAINT fk_security_event_session FOREIGN KEY (session_id) REFERENCES user_session(session_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_security_event_user_occurred_at
+    ON security_event (user_id, occurred_at DESC);
+CREATE INDEX IF NOT EXISTS idx_security_event_type_occurred_at
+    ON security_event (event_type, occurred_at DESC);
+
+-- 批量下载任务：支持大目录异步打包下载
+CREATE TABLE IF NOT EXISTS batch_download_task (
+    task_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    archive_name VARCHAR(255) NOT NULL,
+    item_count INTEGER NOT NULL DEFAULT 0,
+    items JSONB NOT NULL DEFAULT '[]'::jsonb,
+    status VARCHAR(50) NOT NULL DEFAULT 'pending',
+    storage_object_id BIGINT NULL,
+    expire_at TIMESTAMP NULL,
+    error_message TEXT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    completed_at TIMESTAMP NULL,
+    CONSTRAINT fk_batch_download_task_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_batch_download_task_storage_object FOREIGN KEY (storage_object_id) REFERENCES storage_object(object_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_batch_download_task_user_status
+    ON batch_download_task (user_id, status);
+
+DROP TRIGGER IF EXISTS trg_batch_download_task_updated_at ON batch_download_task;
+CREATE TRIGGER trg_batch_download_task_updated_at
+BEFORE UPDATE ON batch_download_task
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+-- 分享访问日志：访问 / 下载统计明细
+CREATE TABLE IF NOT EXISTS share_access_log (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    share_id BIGINT NOT NULL,
+    user_id BIGINT NULL,
+    event_type VARCHAR(20) NOT NULL,
+    ip_address VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    result VARCHAR(20) NOT NULL DEFAULT 'success',
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_share_access_log_share FOREIGN KEY (share_id) REFERENCES share(share_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_access_log_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_share_access_log_share_created_at
+    ON share_access_log (share_id, created_at DESC);
+
+-- =========================
+-- 3) 触发器 / 维护函数
+-- =========================
+
+-- 通知表：同步 is_read / read_at
+CREATE OR REPLACE FUNCTION sync_notification_read_at()
+RETURNS TRIGGER AS $$
+BEGIN
+    IF TG_OP = 'INSERT' THEN
+        IF NEW.is_read AND NEW.read_at IS NULL THEN
+            NEW.read_at = CURRENT_TIMESTAMP;
+        ELSIF NOT NEW.is_read THEN
+            NEW.read_at = NULL;
+        END IF;
+        RETURN NEW;
+    END IF;
+
+    IF NEW.is_read AND (OLD.is_read IS DISTINCT FROM NEW.is_read) AND NEW.read_at IS NULL THEN
+        NEW.read_at = CURRENT_TIMESTAMP;
+    ELSIF NOT NEW.is_read THEN
+        NEW.read_at = NULL;
+    ELSIF NEW.read_at IS NOT NULL THEN
+        NEW.is_read = TRUE;
+    END IF;
+
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_notification_sync_read_at ON notification;
+CREATE TRIGGER trg_notification_sync_read_at
+BEFORE INSERT OR UPDATE ON notification
+FOR EACH ROW
+EXECUTE FUNCTION sync_notification_read_at();
+
+-- 重建 / 维护用户已用空间
+CREATE OR REPLACE FUNCTION recalc_user_storage_used(p_user_id BIGINT)
+RETURNS VOID AS $$
+BEGIN
+    IF p_user_id IS NULL THEN
+        RETURN;
+    END IF;
+
+    UPDATE "user" u
+    SET storage_used = COALESCE((
+        SELECT SUM(f.file_size)
+        FROM "file" f
+        WHERE f.owner_id = p_user_id
+          AND f.status = 'active'
+    ), 0)
+    WHERE u.user_id = p_user_id;
+END;
+$$ LANGUAGE plpgsql;
+
+-- 重建 / 维护物理对象引用数
+CREATE OR REPLACE FUNCTION recalc_storage_object_ref_count(p_object_id BIGINT)
+RETURNS VOID AS $$
+BEGIN
+    IF p_object_id IS NULL THEN
+        RETURN;
+    END IF;
+
+    UPDATE storage_object so
+    SET ref_count = COALESCE((
+        SELECT COUNT(*)
+        FROM "file" f
+        WHERE f.storage_object_id = p_object_id
+          AND f.status = 'active'
+    ), 0)
+    WHERE so.object_id = p_object_id;
+END;
+$$ LANGUAGE plpgsql;
+
+-- 单个目录及其祖先目录大小回算（cached_size = 直属 active 文件大小 + 直属 active 子目录 cached_size）
+CREATE OR REPLACE FUNCTION recalc_folder_cached_size(p_folder_id BIGINT)
+RETURNS VOID AS $$
+DECLARE
+    v_folder_id BIGINT := p_folder_id;
+    v_parent_id BIGINT;
+BEGIN
+    WHILE v_folder_id IS NOT NULL LOOP
+        UPDATE folder f
+        SET cached_size =
+            COALESCE((
+                SELECT SUM(fi.file_size)
+                FROM "file" fi
+                WHERE fi.folder_id = f.folder_id
+                  AND fi.status = 'active'
+            ), 0)
+            +
+            COALESCE((
+                SELECT SUM(ch.cached_size)
+                FROM folder ch
+                WHERE ch.parent_folder_id = f.folder_id
+                  AND ch.status = 'active'
+            ), 0)
+        WHERE f.folder_id = v_folder_id;
+
+        SELECT parent_folder_id INTO v_parent_id
+        FROM folder
+        WHERE folder_id = v_folder_id;
+
+        v_folder_id := v_parent_id;
+    END LOOP;
+END;
+$$ LANGUAGE plpgsql;
+
+-- 全量重建目录缓存大小
+CREATE OR REPLACE FUNCTION rebuild_all_folder_cached_size()
+RETURNS VOID AS $$
+DECLARE
+    r RECORD;
+BEGIN
+    FOR r IN
+        WITH RECURSIVE tree AS (
+            SELECT folder_id, parent_folder_id, 0 AS depth
+            FROM folder
+            WHERE parent_folder_id IS NULL
+
+            UNION ALL
+
+            SELECT f.folder_id, f.parent_folder_id, t.depth + 1
+            FROM folder f
+            JOIN tree t ON f.parent_folder_id = t.folder_id
+        )
+        SELECT folder_id
+        FROM tree
+        ORDER BY depth DESC, folder_id DESC
+    LOOP
+        PERFORM recalc_folder_cached_size(r.folder_id);
+    END LOOP;
+END;
+$$ LANGUAGE plpgsql;
+
+-- 文件夹结构校验：同 owner、不能挂到自己的子孙目录下
+CREATE OR REPLACE FUNCTION check_folder_parent_valid()
+RETURNS TRIGGER AS $$
+DECLARE
+    v_parent_owner BIGINT;
+    v_parent_status folder_status_enum;
+    v_has_cycle BOOLEAN := FALSE;
+BEGIN
+    IF NEW.parent_folder_id IS NULL THEN
+        RETURN NEW;
+    END IF;
+
+    SELECT owner_id, status
+      INTO v_parent_owner, v_parent_status
+    FROM folder
+    WHERE folder_id = NEW.parent_folder_id;
+
+    IF NOT FOUND THEN
+        RAISE EXCEPTION 'Parent folder % does not exist', NEW.parent_folder_id;
+    END IF;
+
+    IF v_parent_owner <> NEW.owner_id THEN
+        RAISE EXCEPTION 'Parent folder owner must match folder owner';
+    END IF;
+
+    IF NEW.status = 'active' AND v_parent_status <> 'active' THEN
+        RAISE EXCEPTION 'Active folder cannot be placed under a non-active parent folder';
+    END IF;
+
+    IF NEW.folder_id IS NOT NULL THEN
+        IF NEW.parent_folder_id = NEW.folder_id THEN
+            RAISE EXCEPTION 'Folder cannot be its own parent';
+        END IF;
+
+        WITH RECURSIVE descendants AS (
+            SELECT folder_id
+            FROM folder
+            WHERE parent_folder_id = NEW.folder_id
+
+            UNION ALL
+
+            SELECT f.folder_id
+            FROM folder f
+            JOIN descendants d ON f.parent_folder_id = d.folder_id
+        )
+        SELECT EXISTS(
+            SELECT 1
+            FROM descendants
+            WHERE folder_id = NEW.parent_folder_id
+        )
+        INTO v_has_cycle;
+
+        IF v_has_cycle THEN
+            RAISE EXCEPTION 'Folder cannot be moved into its own descendant';
+        END IF;
+    END IF;
+
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_folder_validate ON folder;
+CREATE TRIGGER trg_folder_validate
+BEFORE INSERT OR UPDATE OF parent_folder_id, owner_id, status ON folder
+FOR EACH ROW
+EXECUTE FUNCTION check_folder_parent_valid();
+
+-- 文件落目录校验：active 文件必须落在 active 且同 owner 的目录下
+CREATE OR REPLACE FUNCTION check_file_folder_valid()
+RETURNS TRIGGER AS $$
+DECLARE
+    v_folder_owner BIGINT;
+    v_folder_status folder_status_enum;
+BEGIN
+    SELECT owner_id, status
+      INTO v_folder_owner, v_folder_status
+    FROM folder
+    WHERE folder_id = NEW.folder_id;
+
+    IF NOT FOUND THEN
+        RAISE EXCEPTION 'Folder % does not exist', NEW.folder_id;
+    END IF;
+
+    IF NEW.status = 'active' THEN
+        IF v_folder_owner <> NEW.owner_id THEN
+            RAISE EXCEPTION 'File owner must match folder owner';
+        END IF;
+
+        IF v_folder_status <> 'active' THEN
+            RAISE EXCEPTION 'Active file cannot be placed under a non-active folder';
+        END IF;
+    END IF;
+
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_file_validate ON "file";
+CREATE TRIGGER trg_file_validate
+BEFORE INSERT OR UPDATE OF folder_id, owner_id, status ON "file"
+FOR EACH ROW
+EXECUTE FUNCTION check_file_folder_valid();
+
+-- 文件变更后：回算 storage_object.ref_count、user.storage_used、folder.cached_size
+CREATE OR REPLACE FUNCTION sync_file_derived_fields()
+RETURNS TRIGGER AS $$
+BEGIN
+    IF TG_OP = 'INSERT' THEN
+        PERFORM recalc_storage_object_ref_count(NEW.storage_object_id);
+        PERFORM recalc_user_storage_used(NEW.owner_id);
+        PERFORM recalc_folder_cached_size(NEW.folder_id);
+        RETURN NULL;
+    ELSIF TG_OP = 'UPDATE' THEN
+        PERFORM recalc_storage_object_ref_count(OLD.storage_object_id);
+        IF NEW.storage_object_id IS DISTINCT FROM OLD.storage_object_id THEN
+            PERFORM recalc_storage_object_ref_count(NEW.storage_object_id);
+        END IF;
+
+        PERFORM recalc_user_storage_used(OLD.owner_id);
+        IF NEW.owner_id IS DISTINCT FROM OLD.owner_id THEN
+            PERFORM recalc_user_storage_used(NEW.owner_id);
+        END IF;
+
+        PERFORM recalc_folder_cached_size(OLD.folder_id);
+        IF NEW.folder_id IS DISTINCT FROM OLD.folder_id THEN
+            PERFORM recalc_folder_cached_size(NEW.folder_id);
+        END IF;
+        RETURN NULL;
+    ELSE
+        PERFORM recalc_storage_object_ref_count(OLD.storage_object_id);
+        PERFORM recalc_user_storage_used(OLD.owner_id);
+        PERFORM recalc_folder_cached_size(OLD.folder_id);
+        RETURN NULL;
+    END IF;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_file_sync_derived_fields ON "file";
+CREATE TRIGGER trg_file_sync_derived_fields
+AFTER INSERT OR UPDATE OR DELETE ON "file"
+FOR EACH ROW
+EXECUTE FUNCTION sync_file_derived_fields();
+
+-- 目录结构变化后：回算目录大小
+CREATE OR REPLACE FUNCTION sync_folder_cached_size()
+RETURNS TRIGGER AS $$
+BEGIN
+    IF TG_OP = 'INSERT' THEN
+        PERFORM recalc_folder_cached_size(NEW.folder_id);
+        PERFORM recalc_folder_cached_size(NEW.parent_folder_id);
+        RETURN NULL;
+    ELSIF TG_OP = 'UPDATE' THEN
+        PERFORM recalc_folder_cached_size(OLD.parent_folder_id);
+        PERFORM recalc_folder_cached_size(NEW.folder_id);
+        IF NEW.parent_folder_id IS DISTINCT FROM OLD.parent_folder_id THEN
+            PERFORM recalc_folder_cached_size(NEW.parent_folder_id);
+        END IF;
+        RETURN NULL;
+    ELSE
+        PERFORM recalc_folder_cached_size(OLD.parent_folder_id);
+        RETURN NULL;
+    END IF;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_folder_sync_cached_size ON folder;
+CREATE TRIGGER trg_folder_sync_cached_size
+AFTER INSERT OR DELETE OR UPDATE OF parent_folder_id, status ON folder
+FOR EACH ROW
+EXECUTE FUNCTION sync_folder_cached_size();
+
+-- =========================
+-- 4) 初始化缓存字段
+-- =========================
+
+UPDATE storage_object so
+SET ref_count = x.ref_count
+FROM (
+    SELECT storage_object_id, COUNT(*) AS ref_count
+    FROM "file"
+    WHERE status = 'active'
+    GROUP BY storage_object_id
+) x
+WHERE so.object_id = x.storage_object_id;
+
+UPDATE storage_object so
+SET ref_count = 0
+WHERE NOT EXISTS (
+    SELECT 1
+    FROM "file" f
+    WHERE f.storage_object_id = so.object_id
+      AND f.status = 'active'
+);
+
+UPDATE "user" u
+SET storage_used = x.total_size
+FROM (
+    SELECT owner_id AS user_id, COALESCE(SUM(file_size), 0) AS total_size
+    FROM "file"
+    WHERE status = 'active'
+    GROUP BY owner_id
+) x
+WHERE u.user_id = x.user_id;
+
+UPDATE "user" u
+SET storage_used = 0
+WHERE NOT EXISTS (
+    SELECT 1
+    FROM "file" f
+    WHERE f.owner_id = u.user_id
+      AND f.status = 'active'
+);
+
+SELECT rebuild_all_folder_cached_size();
+
+-- =========================
+-- 5) 视图重建
+-- =========================
+DROP VIEW IF EXISTS v_shared_with_me;
+DROP VIEW IF EXISTS v_user_permissions;
+DROP VIEW IF EXISTS v_user_recycle_bin;
+DROP VIEW IF EXISTS v_full_path;
+DROP VIEW IF EXISTS v_file_folder_details;
+DROP VIEW IF EXISTS v_user_storage_summary;
+DROP VIEW IF EXISTS v_admin_share_overview;
+DROP VIEW IF EXISTS v_user_dashboard;
+
+-- 文件 / 文件夹统一明细视图
+CREATE VIEW v_file_folder_details AS
+SELECT
+    'file' AS item_type,
+    f.file_id AS id,
+    f.file_name AS name,
+    f.file_size AS size,
+    f.mime_type,
+    f.folder_id AS parent_id,
+    f.owner_id,
+    u.username AS owner_name,
+    f.created_at,
+    f.updated_at
+FROM "file" f
+JOIN "user" u ON f.owner_id = u.user_id
+JOIN storage_object so ON f.storage_object_id = so.object_id
+WHERE f.status = 'active'
+  AND so.upload_status = 'active'
+
+UNION ALL
+
+SELECT
+    'folder' AS item_type,
+    fo.folder_id AS id,
+    fo.folder_name AS name,
+    fo.cached_size AS size,
+    'inode/directory' AS mime_type,
+    fo.parent_folder_id AS parent_id,
+    fo.owner_id,
+    u.username AS owner_name,
+    fo.created_at,
+    fo.updated_at
+FROM folder fo
+JOIN "user" u ON fo.owner_id = u.user_id
+WHERE fo.status = 'active';
+
+-- 用户权限视图：同时展开 direct user 授权和 group 授权
+CREATE VIEW v_user_permissions AS
+SELECT
+    acl.id AS acl_id,
+    u.user_id,
+    u.username AS user_name,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    CASE WHEN acl.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    acl.permission_role,
+    acl.can_preview,
+    acl.can_download,
+    acl.can_save,
+    acl.can_share,
+    acl.expire_at,
+    'direct'::TEXT AS grant_source
+FROM acl
+JOIN "user" u ON acl.user_id = u.user_id
+LEFT JOIN "file" f ON acl.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON acl.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE acl.user_id IS NOT NULL
+  AND (
+      (acl.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (acl.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  )
+
+UNION ALL
+
+SELECT
+    acl.id AS acl_id,
+    u.user_id,
+    u.username AS user_name,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    CASE WHEN acl.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    acl.permission_role,
+    acl.can_preview,
+    acl.can_download,
+    acl.can_save,
+    acl.can_share,
+    acl.expire_at,
+    'group'::TEXT AS grant_source
+FROM acl
+JOIN user_group_member ugm ON acl.group_id = ugm.group_id
+JOIN "user" u ON ugm.user_id = u.user_id
+LEFT JOIN "file" f ON acl.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON acl.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE acl.group_id IS NOT NULL
+  AND (
+      (acl.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (acl.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  );
+
+-- 用户空间汇总
+CREATE VIEW v_user_storage_summary AS
+SELECT
+    user_id,
+    username,
+    status,
+    storage_limit,
+    storage_used,
+    CASE
+        WHEN storage_limit <= 0 THEN 0::NUMERIC(10,2)
+        ELSE ROUND((storage_used::NUMERIC / storage_limit::NUMERIC) * 100, 2)
+    END AS storage_used_pct
+FROM "user";
+
+-- “共享给我”：基于 share + share_member，包含待接受 / 已接受两种状态
+CREATE VIEW v_shared_with_me AS
+SELECT
+    s.share_id,
+    CASE WHEN s.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    owner.user_id AS shared_by_user_id,
+    owner.username AS shared_by,
+    sm.user_id AS shared_to_user_id,
+    sm.status AS member_status,
+    s.share_type,
+    s.permission_role,
+    s.allow_preview,
+    s.allow_download,
+    s.allow_save,
+    s.allow_reshare,
+    sm.target_folder_id,
+    sm.accepted_at,
+    s.expire_time,
+    s.created_at AS shared_at
+FROM share s
+JOIN share_member sm ON s.share_id = sm.share_id
+JOIN "user" owner ON s.user_id = owner.user_id
+LEFT JOIN "file" f ON s.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON s.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE sm.user_id IS NOT NULL
+  AND sm.status IN ('pending', 'accepted')
+  AND s.status = 'active'
+  AND (s.expire_time IS NULL OR s.expire_time > CURRENT_TIMESTAMP)
+  AND (
+      (s.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (s.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  )
+
+UNION ALL
+
+SELECT
+    s.share_id,
+    CASE WHEN s.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    owner.user_id AS shared_by_user_id,
+    owner.username AS shared_by,
+    ugm.user_id AS shared_to_user_id,
+    sm.status AS member_status,
+    s.share_type,
+    s.permission_role,
+    s.allow_preview,
+    s.allow_download,
+    s.allow_save,
+    s.allow_reshare,
+    sm.target_folder_id,
+    sm.accepted_at,
+    s.expire_time,
+    s.created_at AS shared_at
+FROM share s
+JOIN share_member sm ON s.share_id = sm.share_id
+JOIN user_group_member ugm ON sm.group_id = ugm.group_id
+JOIN "user" owner ON s.user_id = owner.user_id
+LEFT JOIN "file" f ON s.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON s.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE sm.group_id IS NOT NULL
+  AND sm.status IN ('pending', 'accepted')
+  AND s.status = 'active'
+  AND (s.expire_time IS NULL OR s.expire_time > CURRENT_TIMESTAMP)
+  AND (
+      (s.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (s.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  );
+
+-- 目录全路径：按 owner 隔离，且只看 active 目录
+CREATE VIEW v_full_path AS
+WITH RECURSIVE folder_path AS (
+    SELECT
+        folder_id,
+        owner_id,
+        parent_folder_id,
+        folder_name,
+        CAST(folder_name AS VARCHAR(2048)) AS path
+    FROM folder
+    WHERE parent_folder_id IS NULL
+      AND status = 'active'
+
+    UNION ALL
+
+    SELECT
+        f.folder_id,
+        f.owner_id,
+        f.parent_folder_id,
+        f.folder_name,
+        fp.path || '/' || f.folder_name AS path
+    FROM folder f
+    JOIN folder_path fp
+      ON f.parent_folder_id = fp.folder_id
+     AND f.owner_id = fp.owner_id
+    WHERE f.status = 'active'
+)
+SELECT
+    folder_id AS id,
+    owner_id,
+    parent_folder_id,
+    path
+FROM folder_path;
+
+-- 回收站视图：修正 file.owner_id，并改用 cached_size
+CREATE VIEW v_user_recycle_bin AS
+SELECT
+    'file' AS item_type,
+    f.file_id AS id,
+    f.file_name AS name,
+    f.file_size AS size,
+    f.folder_id AS parent_id,
+    f.owner_id,
+    u.username AS owner_name,
+    f.deleted_at
+FROM "file" f
+JOIN "user" u ON f.owner_id = u.user_id
+WHERE f.status = 'deleted'
+  AND f.deleted_at IS NOT NULL
+
+UNION ALL
+
+SELECT
+    'folder' AS item_type,
+    fo.folder_id AS id,
+    fo.folder_name AS name,
+    fo.cached_size AS size,
+    fo.parent_folder_id AS parent_id,
+    fo.owner_id,
+    u.username AS owner_name,
+    fo.deleted_at
+FROM folder fo
+JOIN "user" u ON fo.owner_id = u.user_id
+WHERE fo.status = 'deleted'
+  AND fo.deleted_at IS NOT NULL;
+
+-- 管理员查看分享链接总览
+CREATE VIEW v_admin_share_overview AS
+SELECT
+    s.share_id,
+    s.share_code,
+    s.status,
+    s.share_type,
+    s.user_id AS created_by_user_id,
+    u.username AS created_by,
+    CASE WHEN s.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    s.permission_role,
+    s.allow_preview,
+    s.allow_download,
+    s.allow_save,
+    s.allow_reshare,
+    s.require_login,
+    s.password_hash IS NOT NULL AS has_password,
+    s.expire_time,
+    s.visit_count,
+    s.download_count,
+    s.created_at,
+    s.updated_at
+FROM share s
+JOIN "user" u ON s.user_id = u.user_id
+LEFT JOIN "file" f ON s.file_id = f.file_id
+LEFT JOIN folder fo ON s.folder_id = fo.folder_id;
+
+-- 管理员用户仪表盘
+CREATE VIEW v_user_dashboard AS
+SELECT
+    u.user_id,
+    u.username,
+    u.email,
+    u.status,
+    u.storage_limit,
+    u.storage_used,
+    CASE
+        WHEN u.storage_limit <= 0 THEN 0::NUMERIC(10,2)
+        ELSE ROUND((u.storage_used::NUMERIC / u.storage_limit::NUMERIC) * 100, 2)
+    END AS storage_used_pct,
+    COALESCE(f.file_count, 0) AS active_file_count,
+    COALESCE(fo.folder_count, 0) AS active_folder_count,
+    COALESCE(s.active_share_count, 0) AS active_share_count,
+    COALESCE(fv.favorite_count, 0) AS favorite_count,
+    u.last_login_at,
+    u.created_at
+FROM "user" u
+LEFT JOIN (
+    SELECT owner_id, COUNT(*) AS file_count
+    FROM "file"
+    WHERE status = 'active'
+    GROUP BY owner_id
+) f ON u.user_id = f.owner_id
+LEFT JOIN (
+    SELECT owner_id, COUNT(*) AS folder_count
+    FROM folder
+    WHERE status = 'active'
+    GROUP BY owner_id
+) fo ON u.user_id = fo.owner_id
+LEFT JOIN (
+    SELECT user_id, COUNT(*) AS active_share_count
+    FROM share
+    WHERE status = 'active'
+      AND (expire_time IS NULL OR expire_time > CURRENT_TIMESTAMP)
+    GROUP BY user_id
+) s ON u.user_id = s.user_id
+LEFT JOIN (
+    SELECT user_id, COUNT(*) AS favorite_count
+    FROM favorite_item
+    GROUP BY user_id
+) fv ON u.user_id = fv.user_id;
diff --git a/docs/schema-summary.sql b/docs/schema-summary.sql
new file mode 100644
index 0000000..c889a71
--- /dev/null
+++ b/docs/schema-summary.sql
@@ -0,0 +1,11 @@
+-- PostgreSQL schema entrypoint (domain-splitted)
+-- Usage (from repository root):
+--   psql -U <user> -d <db> -f docs/schema-postgres.sql
+
+\ir sql/postgres/00_base.sql
+\ir sql/postgres/10_identity.sql
+\ir sql/postgres/20_storage.sql
+\ir sql/postgres/30_access_share.sql
+\ir sql/postgres/40_audit_security.sql
+\ir sql/postgres/50_maintenance_views.sql
+\ir sql/postgres/90_comments.sql
diff --git a/docs/sql/postgres/00_base.sql b/docs/sql/postgres/00_base.sql
new file mode 100644
index 0000000..c8eccef
--- /dev/null
+++ b/docs/sql/postgres/00_base.sql
@@ -0,0 +1,81 @@
+-- =========================
+-- Base: extensions, enum types, common trigger functions
+-- =========================
+
+CREATE EXTENSION IF NOT EXISTS pg_trgm;
+
+DO $$
+BEGIN
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'upload_status_enum') THEN
+        CREATE TYPE upload_status_enum AS ENUM ('uploading', 'active', 'deleted', 'failed');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'folder_status_enum') THEN
+        CREATE TYPE folder_status_enum AS ENUM ('active', 'deleted');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'file_status_enum') THEN
+        CREATE TYPE file_status_enum AS ENUM ('active', 'deleted');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'upload_mode_enum') THEN
+        CREATE TYPE upload_mode_enum AS ENUM ('single', 'multipart');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'upload_task_status_enum') THEN
+        CREATE TYPE upload_task_status_enum AS ENUM ('init', 'uploading', 'completed', 'aborted', 'failed');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'upload_part_status_enum') THEN
+        CREATE TYPE upload_part_status_enum AS ENUM ('pending', 'uploaded', 'failed');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'user_status_enum') THEN
+        CREATE TYPE user_status_enum AS ENUM ('pending_verification', 'active', 'locked', 'disabled');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'folder_type_enum') THEN
+        CREATE TYPE folder_type_enum AS ENUM ('normal', 'root', 'system');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'share_status_enum') THEN
+        CREATE TYPE share_status_enum AS ENUM ('active', 'expired', 'revoked', 'deleted');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'share_member_status_enum') THEN
+        CREATE TYPE share_member_status_enum AS ENUM ('pending', 'accepted', 'rejected', 'revoked');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'favorite_item_type_enum') THEN
+        CREATE TYPE favorite_item_type_enum AS ENUM ('file', 'folder');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'view_mode_enum') THEN
+        CREATE TYPE view_mode_enum AS ENUM ('list', 'grid');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'sort_by_enum') THEN
+        CREATE TYPE sort_by_enum AS ENUM ('name', 'size', 'created_at', 'updated_at', 'last_accessed_at');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'sort_direction_enum') THEN
+        CREATE TYPE sort_direction_enum AS ENUM ('asc', 'desc');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'preview_status_enum') THEN
+        CREATE TYPE preview_status_enum AS ENUM ('pending', 'ready', 'failed');
+    END IF;
+
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'scan_result_enum') THEN
+        CREATE TYPE scan_result_enum AS ENUM ('pending', 'clean', 'infected', 'blocked', 'failed');
+    END IF;
+END
+$$;
+
+CREATE OR REPLACE FUNCTION set_updated_at()
+RETURNS TRIGGER AS $$
+BEGIN
+    NEW.updated_at = CURRENT_TIMESTAMP;
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
diff --git a/docs/sql/postgres/10_identity.sql b/docs/sql/postgres/10_identity.sql
new file mode 100644
index 0000000..9e96660
--- /dev/null
+++ b/docs/sql/postgres/10_identity.sql
@@ -0,0 +1,96 @@
+-- =========================
+-- Domain: identity
+-- =========================
+
+CREATE TABLE IF NOT EXISTS "user" (
+    user_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    username VARCHAR(100) NOT NULL,
+    email VARCHAR(255) NOT NULL,
+    password_hash VARCHAR(255) NOT NULL,
+    role VARCHAR(50) NOT NULL DEFAULT 'USER',
+    status user_status_enum NOT NULL DEFAULT 'active',
+    email_verified BOOLEAN NOT NULL DEFAULT FALSE,
+    email_verified_at TIMESTAMP NULL,
+    storage_limit BIGINT NOT NULL DEFAULT 10737418240,
+    storage_used BIGINT NOT NULL DEFAULT 0,
+    last_login_at TIMESTAMP NULL,
+    failed_login_count INTEGER NOT NULL DEFAULT 0,
+    locked_until TIMESTAMP NULL,
+    password_changed_at TIMESTAMP NULL,
+    deleted_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_username_ci ON "user" ((LOWER(username)));
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_email_ci ON "user" ((LOWER(email)));
+CREATE INDEX IF NOT EXISTS idx_user_status ON "user" (status);
+CREATE INDEX IF NOT EXISTS idx_user_locked_until ON "user" (locked_until);
+
+CREATE TRIGGER trg_user_updated_at
+BEFORE UPDATE ON "user"
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS user_group (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    name VARCHAR(100) NOT NULL UNIQUE,
+    description VARCHAR(255)
+);
+
+CREATE TABLE IF NOT EXISTS user_group_member (
+    id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    group_id BIGINT NOT NULL,
+    role VARCHAR(50) NOT NULL DEFAULT 'member',
+    CONSTRAINT fk_ugm_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_ugm_group FOREIGN KEY (group_id) REFERENCES user_group(id) ON DELETE CASCADE,
+    CONSTRAINT uk_user_group UNIQUE (user_id, group_id)
+);
+
+CREATE TABLE IF NOT EXISTS password_reset_token (
+    token_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    token_hash CHAR(64) NOT NULL UNIQUE,
+    expire_at TIMESTAMP NOT NULL,
+    used_at TIMESTAMP NULL,
+    requester_ip VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_password_reset_token_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_password_reset_token_user_expire
+    ON password_reset_token (user_id, expire_at);
+
+CREATE TABLE IF NOT EXISTS email_verification_token (
+    token_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    token_hash CHAR(64) NOT NULL UNIQUE,
+    expire_at TIMESTAMP NOT NULL,
+    verified_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_email_verification_token_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_email_verification_token_user_expire
+    ON email_verification_token (user_id, expire_at);
+
+CREATE TABLE IF NOT EXISTS user_session (
+    session_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    refresh_token_hash CHAR(64) NOT NULL UNIQUE,
+    client_type VARCHAR(50) NOT NULL DEFAULT 'web',
+    device_id VARCHAR(255) NULL,
+    device_name VARCHAR(255) NULL,
+    ip_address VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    last_seen_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    expire_at TIMESTAMP NOT NULL,
+    revoked_at TIMESTAMP NULL,
+    CONSTRAINT fk_user_session_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_user_session_user_expire
+    ON user_session (user_id, expire_at);
diff --git a/docs/sql/postgres/20_storage.sql b/docs/sql/postgres/20_storage.sql
new file mode 100644
index 0000000..5fee641
--- /dev/null
+++ b/docs/sql/postgres/20_storage.sql
@@ -0,0 +1,241 @@
+-- =========================
+-- Domain: storage and upload
+-- =========================
+
+CREATE TABLE IF NOT EXISTS storage_object (
+    object_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    object_hash CHAR(64),
+    hash_algorithm VARCHAR(32) NOT NULL DEFAULT 'sha256',
+    bucket_name VARCHAR(100) NOT NULL,
+    object_key VARCHAR(1024) NOT NULL,
+    object_size BIGINT NOT NULL,
+    etag VARCHAR(128),
+    version_id VARCHAR(255),
+    content_type VARCHAR(255),
+    storage_class VARCHAR(50),
+    upload_status upload_status_enum NOT NULL DEFAULT 'active',
+    scan_status scan_result_enum NOT NULL DEFAULT 'pending',
+    moderation_status VARCHAR(32) NOT NULL DEFAULT 'pending',
+    quarantined_at TIMESTAMP NULL,
+    last_scanned_at TIMESTAMP NULL,
+    metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
+    ref_count INTEGER NOT NULL DEFAULT 1,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    deleted_at TIMESTAMP NULL,
+    CONSTRAINT uk_bucket_object_key UNIQUE (bucket_name, object_key)
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_storage_object_hash_algo_size
+    ON storage_object (hash_algorithm, object_hash, object_size)
+    WHERE object_hash IS NOT NULL;
+
+CREATE INDEX IF NOT EXISTS idx_storage_object_scan_status ON storage_object (scan_status);
+CREATE INDEX IF NOT EXISTS idx_storage_object_moderation_status ON storage_object (moderation_status);
+CREATE INDEX IF NOT EXISTS idx_storage_object_upload_status ON storage_object(upload_status);
+
+CREATE TRIGGER trg_storage_object_updated_at
+BEFORE UPDATE ON storage_object
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS folder (
+    folder_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    owner_id BIGINT NOT NULL,
+    parent_folder_id BIGINT NULL,
+    folder_name VARCHAR(255) NOT NULL,
+    cached_size BIGINT NOT NULL DEFAULT 0,
+    status folder_status_enum NOT NULL DEFAULT 'active',
+    folder_type folder_type_enum NOT NULL DEFAULT 'normal',
+    deleted_by BIGINT NULL,
+    restored_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    deleted_at TIMESTAMP NULL,
+    CONSTRAINT fk_folder_owner FOREIGN KEY (owner_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_folder_parent FOREIGN KEY (parent_folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
+    CONSTRAINT fk_folder_deleted_by FOREIGN KEY (deleted_by) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_folder_root_name_active
+    ON folder (owner_id, folder_name)
+    WHERE parent_folder_id IS NULL AND status = 'active';
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_folder_child_name_active
+    ON folder (owner_id, parent_folder_id, folder_name)
+    WHERE parent_folder_id IS NOT NULL AND status = 'active';
+
+CREATE INDEX IF NOT EXISTS idx_folder_owner_parent_status ON folder (owner_id, parent_folder_id, status);
+CREATE INDEX IF NOT EXISTS idx_folder_name_trgm ON folder USING gin ((LOWER(folder_name)) gin_trgm_ops);
+
+CREATE TRIGGER trg_folder_updated_at
+BEFORE UPDATE ON folder
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS "file" (
+    file_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    uploader_id BIGINT NOT NULL,
+    owner_id BIGINT NOT NULL,
+    folder_id BIGINT NOT NULL,
+    file_name VARCHAR(255) NOT NULL,
+    file_ext VARCHAR(50),
+    mime_type VARCHAR(255),
+    storage_object_id BIGINT NOT NULL,
+    file_size BIGINT NOT NULL,
+    is_latest BOOLEAN NOT NULL DEFAULT TRUE,
+    status file_status_enum NOT NULL DEFAULT 'active',
+    deleted_by BIGINT NULL,
+    restored_at TIMESTAMP NULL,
+    last_accessed_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    deleted_at TIMESTAMP NULL,
+    CONSTRAINT fk_file_uploader FOREIGN KEY (uploader_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_file_owner FOREIGN KEY (owner_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_file_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
+    CONSTRAINT fk_file_storage_object FOREIGN KEY (storage_object_id) REFERENCES storage_object(object_id),
+    CONSTRAINT fk_file_deleted_by FOREIGN KEY (deleted_by) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_file_name_active_in_folder
+    ON "file" (owner_id, folder_id, file_name)
+    WHERE status = 'active';
+
+CREATE INDEX IF NOT EXISTS idx_file_last_accessed_at ON "file" (last_accessed_at);
+CREATE INDEX IF NOT EXISTS idx_file_name_trgm ON "file" USING gin ((LOWER(file_name)) gin_trgm_ops);
+CREATE INDEX IF NOT EXISTS idx_file_storage_object_id ON "file"(storage_object_id);
+CREATE INDEX IF NOT EXISTS idx_file_owner_folder ON "file"(owner_id, folder_id, status);
+
+CREATE TRIGGER trg_file_updated_at
+BEFORE UPDATE ON "file"
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS upload_task (
+    task_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    folder_id BIGINT NULL,
+    file_name VARCHAR(255) NULL,
+    mime_type VARCHAR(255) NULL,
+    bucket_name VARCHAR(100) NOT NULL,
+    object_key VARCHAR(1024) NOT NULL,
+    object_hash CHAR(64),
+    total_size BIGINT NOT NULL,
+    chunk_size BIGINT NULL,
+    uploaded_bytes BIGINT NOT NULL DEFAULT 0,
+    client_file_id VARCHAR(255) NULL,
+    upload_id VARCHAR(255),
+    upload_mode upload_mode_enum NOT NULL DEFAULT 'single',
+    status upload_task_status_enum NOT NULL DEFAULT 'init',
+    last_error TEXT NULL,
+    completed_at TIMESTAMP NULL,
+    expired_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_upload_task_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_upload_task_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE SET NULL,
+    CONSTRAINT uk_upload_target UNIQUE (bucket_name, object_key, upload_id)
+);
+
+CREATE INDEX IF NOT EXISTS idx_upload_task_user_status ON upload_task(user_id, status);
+CREATE INDEX IF NOT EXISTS idx_upload_task_expired_at ON upload_task (expired_at);
+CREATE UNIQUE INDEX IF NOT EXISTS uk_upload_task_user_client_file_id
+    ON upload_task (user_id, client_file_id)
+    WHERE client_file_id IS NOT NULL;
+
+CREATE TRIGGER trg_upload_task_updated_at
+BEFORE UPDATE ON upload_task
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS upload_task_part (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    task_id BIGINT NOT NULL,
+    part_number INTEGER NOT NULL,
+    etag VARCHAR(128),
+    part_size BIGINT NOT NULL,
+    status upload_part_status_enum NOT NULL DEFAULT 'pending',
+    checksum CHAR(64) NULL,
+    uploaded_at TIMESTAMP NULL,
+    retry_count INTEGER NOT NULL DEFAULT 0,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_upload_task_part_task FOREIGN KEY (task_id) REFERENCES upload_task(task_id) ON DELETE CASCADE,
+    CONSTRAINT uk_task_part UNIQUE (task_id, part_number)
+);
+
+CREATE INDEX IF NOT EXISTS idx_upload_task_part_task_status ON upload_task_part (task_id, status);
+
+CREATE TRIGGER trg_upload_task_part_updated_at
+BEFORE UPDATE ON upload_task_part
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS file_preview_asset (
+    preview_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    source_object_id BIGINT NOT NULL,
+    preview_object_id BIGINT NULL,
+    preview_type VARCHAR(50) NOT NULL,
+    page_no INTEGER NULL,
+    mime_type VARCHAR(255) NULL,
+    width INTEGER NULL,
+    height INTEGER NULL,
+    duration_ms BIGINT NULL,
+    status preview_status_enum NOT NULL DEFAULT 'pending',
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_file_preview_asset_source_object FOREIGN KEY (source_object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE,
+    CONSTRAINT fk_file_preview_asset_preview_object FOREIGN KEY (preview_object_id) REFERENCES storage_object(object_id) ON DELETE SET NULL
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_file_preview_asset_type_page
+    ON file_preview_asset (source_object_id, preview_type, (COALESCE(page_no, -1)));
+
+DROP TRIGGER IF EXISTS trg_file_preview_asset_updated_at ON file_preview_asset;
+CREATE TRIGGER trg_file_preview_asset_updated_at
+BEFORE UPDATE ON file_preview_asset
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS file_media_metadata (
+    metadata_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    source_object_id BIGINT NOT NULL UNIQUE,
+    width INTEGER NULL,
+    height INTEGER NULL,
+    duration_ms BIGINT NULL,
+    page_count INTEGER NULL,
+    bitrate INTEGER NULL,
+    sample_rate INTEGER NULL,
+    video_codec VARCHAR(64) NULL,
+    audio_codec VARCHAR(64) NULL,
+    extra_metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
+    extracted_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_file_media_metadata_source_object FOREIGN KEY (source_object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE
+);
+
+CREATE TABLE IF NOT EXISTS batch_download_task (
+    task_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    archive_name VARCHAR(255) NOT NULL,
+    item_count INTEGER NOT NULL DEFAULT 0,
+    items JSONB NOT NULL DEFAULT '[]'::jsonb,
+    status VARCHAR(50) NOT NULL DEFAULT 'pending',
+    storage_object_id BIGINT NULL,
+    expire_at TIMESTAMP NULL,
+    error_message TEXT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    completed_at TIMESTAMP NULL,
+    CONSTRAINT fk_batch_download_task_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_batch_download_task_storage_object FOREIGN KEY (storage_object_id) REFERENCES storage_object(object_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_batch_download_task_user_status
+    ON batch_download_task (user_id, status);
+
+DROP TRIGGER IF EXISTS trg_batch_download_task_updated_at ON batch_download_task;
+CREATE TRIGGER trg_batch_download_task_updated_at
+BEFORE UPDATE ON batch_download_task
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
diff --git a/docs/sql/postgres/30_access_share.sql b/docs/sql/postgres/30_access_share.sql
new file mode 100644
index 0000000..e2fe2e5
--- /dev/null
+++ b/docs/sql/postgres/30_access_share.sql
@@ -0,0 +1,196 @@
+-- =========================
+-- Domain: access control and sharing
+-- =========================
+
+CREATE TABLE IF NOT EXISTS acl (
+    id INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    file_id BIGINT NULL,
+    folder_id BIGINT NULL,
+    user_id BIGINT NULL,
+    group_id BIGINT NULL,
+    permission VARCHAR(100) NOT NULL,
+    permission_role VARCHAR(50) NOT NULL DEFAULT 'viewer',
+    can_preview BOOLEAN NOT NULL DEFAULT TRUE,
+    can_download BOOLEAN NOT NULL DEFAULT TRUE,
+    can_save BOOLEAN NOT NULL DEFAULT FALSE,
+    can_share BOOLEAN NOT NULL DEFAULT FALSE,
+    expire_at TIMESTAMP NULL,
+    granted_by BIGINT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_acl_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE CASCADE,
+    CONSTRAINT fk_acl_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
+    CONSTRAINT fk_acl_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_acl_group FOREIGN KEY (group_id) REFERENCES user_group(id) ON DELETE CASCADE,
+    CONSTRAINT fk_acl_granted_by FOREIGN KEY (granted_by) REFERENCES "user"(user_id) ON DELETE SET NULL,
+    CONSTRAINT chk_acl_subject_exactly_one CHECK (num_nonnulls(user_id, group_id) = 1),
+    CONSTRAINT chk_acl_resource_exactly_one CHECK (num_nonnulls(file_id, folder_id) = 1)
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_file_user
+    ON acl (file_id, user_id)
+    WHERE file_id IS NOT NULL AND user_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_file_group
+    ON acl (file_id, group_id)
+    WHERE file_id IS NOT NULL AND group_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_folder_user
+    ON acl (folder_id, user_id)
+    WHERE folder_id IS NOT NULL AND user_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_acl_folder_group
+    ON acl (folder_id, group_id)
+    WHERE folder_id IS NOT NULL AND group_id IS NOT NULL;
+
+CREATE TRIGGER trg_acl_updated_at
+BEFORE UPDATE ON acl
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS share (
+    share_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    resource_type VARCHAR(50) NOT NULL,
+    file_id BIGINT NULL,
+    folder_id BIGINT NULL,
+    share_link VARCHAR(255) NOT NULL UNIQUE,
+    share_code VARCHAR(64) NOT NULL,
+    status share_status_enum NOT NULL DEFAULT 'active',
+    share_type VARCHAR(50) NOT NULL DEFAULT 'public',
+    permission_role VARCHAR(50) NOT NULL DEFAULT 'viewer',
+    allow_preview BOOLEAN NOT NULL DEFAULT TRUE,
+    allow_download BOOLEAN NOT NULL DEFAULT TRUE,
+    allow_save BOOLEAN NOT NULL DEFAULT FALSE,
+    allow_reshare BOOLEAN NOT NULL DEFAULT FALSE,
+    require_login BOOLEAN NOT NULL DEFAULT FALSE,
+    max_visits INTEGER NULL,
+    max_downloads INTEGER NULL,
+    password_hash VARCHAR(255),
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    last_accessed_at TIMESTAMP NULL,
+    expire_time TIMESTAMP NULL,
+    visit_count INTEGER NOT NULL DEFAULT 0,
+    download_count INTEGER NOT NULL DEFAULT 0,
+    CONSTRAINT fk_share_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
+    CONSTRAINT chk_share_target CHECK (num_nonnulls(file_id, folder_id) = 1),
+    CONSTRAINT chk_share_limits CHECK (
+        (max_visits IS NULL OR max_visits >= 0)
+        AND
+        (max_downloads IS NULL OR max_downloads >= 0)
+    )
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_share_code ON share (share_code);
+CREATE INDEX IF NOT EXISTS idx_share_user_status ON share (user_id, status);
+CREATE INDEX IF NOT EXISTS idx_share_expire_time ON share (expire_time);
+
+CREATE TRIGGER trg_share_updated_at
+BEFORE UPDATE ON share
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS share_member (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    share_id BIGINT NOT NULL,
+    user_id BIGINT NULL,
+    group_id BIGINT NULL,
+    status share_member_status_enum NOT NULL DEFAULT 'pending',
+    target_folder_id BIGINT NULL,
+    accepted_at TIMESTAMP NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_share_member_share FOREIGN KEY (share_id) REFERENCES share(share_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_member_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_member_group FOREIGN KEY (group_id) REFERENCES user_group(id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_member_target_folder FOREIGN KEY (target_folder_id) REFERENCES folder(folder_id) ON DELETE SET NULL,
+    CONSTRAINT chk_share_member_subject_exactly_one CHECK (num_nonnulls(user_id, group_id) = 1)
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_share_member_user
+    ON share_member (share_id, user_id)
+    WHERE user_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_share_member_group
+    ON share_member (share_id, group_id)
+    WHERE group_id IS NOT NULL;
+
+CREATE INDEX IF NOT EXISTS idx_share_member_share_status ON share_member (share_id, status);
+
+DROP TRIGGER IF EXISTS trg_share_member_updated_at ON share_member;
+CREATE TRIGGER trg_share_member_updated_at
+BEFORE UPDATE ON share_member
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS favorite_item (
+    favorite_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    item_type favorite_item_type_enum NOT NULL,
+    file_id BIGINT NULL,
+    folder_id BIGINT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_favorite_item_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_favorite_item_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE CASCADE,
+    CONSTRAINT fk_favorite_item_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE,
+    CONSTRAINT chk_favorite_item_target_exactly_one CHECK (num_nonnulls(file_id, folder_id) = 1),
+    CONSTRAINT chk_favorite_item_type_match CHECK (
+        (item_type = 'file' AND file_id IS NOT NULL AND folder_id IS NULL)
+        OR
+        (item_type = 'folder' AND folder_id IS NOT NULL AND file_id IS NULL)
+    )
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_favorite_item_file
+    ON favorite_item (user_id, file_id)
+    WHERE file_id IS NOT NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_favorite_item_folder
+    ON favorite_item (user_id, folder_id)
+    WHERE folder_id IS NOT NULL;
+
+CREATE TABLE IF NOT EXISTS user_folder_preference (
+    preference_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    folder_id BIGINT NULL,
+    view_mode view_mode_enum NOT NULL DEFAULT 'list',
+    sort_by sort_by_enum NOT NULL DEFAULT 'name',
+    sort_direction sort_direction_enum NOT NULL DEFAULT 'asc',
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_user_folder_preference_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_user_folder_preference_folder FOREIGN KEY (folder_id) REFERENCES folder(folder_id) ON DELETE CASCADE
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_folder_preference_default
+    ON user_folder_preference (user_id)
+    WHERE folder_id IS NULL;
+
+CREATE UNIQUE INDEX IF NOT EXISTS uk_user_folder_preference_folder
+    ON user_folder_preference (user_id, folder_id)
+    WHERE folder_id IS NOT NULL;
+
+DROP TRIGGER IF EXISTS trg_user_folder_preference_updated_at ON user_folder_preference;
+CREATE TRIGGER trg_user_folder_preference_updated_at
+BEFORE UPDATE ON user_folder_preference
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS share_access_log (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    share_id BIGINT NOT NULL,
+    user_id BIGINT NULL,
+    event_type VARCHAR(20) NOT NULL,
+    ip_address VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    result VARCHAR(20) NOT NULL DEFAULT 'success',
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_share_access_log_share FOREIGN KEY (share_id) REFERENCES share(share_id) ON DELETE CASCADE,
+    CONSTRAINT fk_share_access_log_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_share_access_log_share_created_at
+    ON share_access_log (share_id, created_at DESC);
diff --git a/docs/sql/postgres/40_audit_security.sql b/docs/sql/postgres/40_audit_security.sql
new file mode 100644
index 0000000..165ff2e
--- /dev/null
+++ b/docs/sql/postgres/40_audit_security.sql
@@ -0,0 +1,146 @@
+-- =========================
+-- Domain: audit, notification and risk control
+-- =========================
+
+CREATE TABLE IF NOT EXISTS "log" (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NULL,
+    actor_type VARCHAR(50) NOT NULL DEFAULT 'user',
+    operation VARCHAR(255) NOT NULL,
+    target_type VARCHAR(50) NULL,
+    target_id BIGINT NULL,
+    result VARCHAR(20) NOT NULL DEFAULT 'success',
+    request_id VARCHAR(128) NULL,
+    user_agent VARCHAR(255) NULL,
+    metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
+    details TEXT,
+    ip_address VARCHAR(45),
+    performed_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_log_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_log_performed_at ON "log" (performed_at);
+CREATE INDEX IF NOT EXISTS idx_log_user_operation ON "log" (user_id, operation);
+CREATE INDEX IF NOT EXISTS idx_log_target ON "log" (target_type, target_id);
+CREATE INDEX IF NOT EXISTS idx_log_request_id ON "log" (request_id);
+
+CREATE TABLE IF NOT EXISTS notification (
+    id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NOT NULL,
+    title VARCHAR(255) NULL,
+    type VARCHAR(50) NOT NULL DEFAULT 'system',
+    channel VARCHAR(50) NOT NULL DEFAULT 'in_app',
+    message TEXT NOT NULL,
+    payload JSONB NOT NULL DEFAULT '{}'::jsonb,
+    sent_at TIMESTAMP NULL,
+    is_read BOOLEAN DEFAULT FALSE,
+    read_at TIMESTAMP NULL,
+    status VARCHAR(50) NOT NULL DEFAULT 'pending',
+    sender_user_id BIGINT NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_notification_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE CASCADE,
+    CONSTRAINT fk_notification_sender_user FOREIGN KEY (sender_user_id) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_notification_user_status ON notification (user_id, status, is_read);
+CREATE INDEX IF NOT EXISTS idx_notification_created_at ON notification (created_at);
+
+CREATE TRIGGER trg_notification_updated_at
+BEFORE UPDATE ON notification
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE OR REPLACE FUNCTION sync_notification_read_at()
+RETURNS TRIGGER AS $$
+BEGIN
+    IF TG_OP = 'INSERT' THEN
+        IF NEW.is_read AND NEW.read_at IS NULL THEN
+            NEW.read_at = CURRENT_TIMESTAMP;
+        ELSIF NOT NEW.is_read THEN
+            NEW.read_at = NULL;
+        END IF;
+        RETURN NEW;
+    END IF;
+
+    IF NEW.is_read AND (OLD.is_read IS DISTINCT FROM NEW.is_read) AND NEW.read_at IS NULL THEN
+        NEW.read_at = CURRENT_TIMESTAMP;
+    ELSIF NOT NEW.is_read THEN
+        NEW.read_at = NULL;
+    ELSIF NEW.read_at IS NOT NULL THEN
+        NEW.is_read = TRUE;
+    END IF;
+
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_notification_sync_read_at ON notification;
+CREATE TRIGGER trg_notification_sync_read_at
+BEFORE INSERT OR UPDATE ON notification
+FOR EACH ROW
+EXECUTE FUNCTION sync_notification_read_at();
+
+CREATE TABLE IF NOT EXISTS object_scan_result (
+    scan_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    object_id BIGINT NOT NULL,
+    scan_type VARCHAR(50) NOT NULL,
+    engine_name VARCHAR(100) NULL,
+    engine_version VARCHAR(100) NULL,
+    result scan_result_enum NOT NULL DEFAULT 'pending',
+    details JSONB NOT NULL DEFAULT '{}'::jsonb,
+    scanned_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_object_scan_result_object FOREIGN KEY (object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE
+);
+
+CREATE INDEX IF NOT EXISTS idx_object_scan_result_object_scanned_at
+    ON object_scan_result (object_id, scanned_at DESC);
+
+CREATE TABLE IF NOT EXISTS moderation_case (
+    case_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    object_id BIGINT NOT NULL,
+    file_id BIGINT NULL,
+    reason_type VARCHAR(50) NOT NULL,
+    confidence NUMERIC(5,4) NULL,
+    status VARCHAR(50) NOT NULL DEFAULT 'pending',
+    resolution VARCHAR(50) NULL,
+    detail JSONB NOT NULL DEFAULT '{}'::jsonb,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    handled_by BIGINT NULL,
+    handled_at TIMESTAMP NULL,
+    CONSTRAINT fk_moderation_case_object FOREIGN KEY (object_id) REFERENCES storage_object(object_id) ON DELETE CASCADE,
+    CONSTRAINT fk_moderation_case_file FOREIGN KEY (file_id) REFERENCES "file"(file_id) ON DELETE SET NULL,
+    CONSTRAINT fk_moderation_case_handled_by FOREIGN KEY (handled_by) REFERENCES "user"(user_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_moderation_case_status_created_at
+    ON moderation_case (status, created_at DESC);
+
+DROP TRIGGER IF EXISTS trg_moderation_case_updated_at ON moderation_case;
+CREATE TRIGGER trg_moderation_case_updated_at
+BEFORE UPDATE ON moderation_case
+FOR EACH ROW
+EXECUTE FUNCTION set_updated_at();
+
+CREATE TABLE IF NOT EXISTS security_event (
+    event_id BIGINT GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY,
+    user_id BIGINT NULL,
+    session_id BIGINT NULL,
+    event_type VARCHAR(50) NOT NULL,
+    severity VARCHAR(20) NOT NULL DEFAULT 'info',
+    target_type VARCHAR(50) NULL,
+    target_id BIGINT NULL,
+    ip_address VARCHAR(45) NULL,
+    user_agent VARCHAR(255) NULL,
+    detail JSONB NOT NULL DEFAULT '{}'::jsonb,
+    occurred_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    CONSTRAINT fk_security_event_user FOREIGN KEY (user_id) REFERENCES "user"(user_id) ON DELETE SET NULL,
+    CONSTRAINT fk_security_event_session FOREIGN KEY (session_id) REFERENCES user_session(session_id) ON DELETE SET NULL
+);
+
+CREATE INDEX IF NOT EXISTS idx_security_event_user_occurred_at
+    ON security_event (user_id, occurred_at DESC);
+CREATE INDEX IF NOT EXISTS idx_security_event_type_occurred_at
+    ON security_event (event_type, occurred_at DESC);
diff --git a/docs/sql/postgres/50_maintenance_views.sql b/docs/sql/postgres/50_maintenance_views.sql
new file mode 100644
index 0000000..978edea
--- /dev/null
+++ b/docs/sql/postgres/50_maintenance_views.sql
@@ -0,0 +1,624 @@
+-- =========================
+-- Domain: maintenance functions and views
+-- =========================
+
+CREATE OR REPLACE FUNCTION recalc_user_storage_used(p_user_id BIGINT)
+RETURNS VOID AS $$
+BEGIN
+    IF p_user_id IS NULL THEN
+        RETURN;
+    END IF;
+
+    UPDATE "user" u
+    SET storage_used = COALESCE((
+        SELECT SUM(f.file_size)
+        FROM "file" f
+        WHERE f.owner_id = p_user_id
+          AND f.status = 'active'
+    ), 0)
+    WHERE u.user_id = p_user_id;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION recalc_storage_object_ref_count(p_object_id BIGINT)
+RETURNS VOID AS $$
+BEGIN
+    IF p_object_id IS NULL THEN
+        RETURN;
+    END IF;
+
+    UPDATE storage_object so
+    SET ref_count = COALESCE((
+        SELECT COUNT(*)
+        FROM "file" f
+        WHERE f.storage_object_id = p_object_id
+          AND f.status = 'active'
+    ), 0)
+    WHERE so.object_id = p_object_id;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION recalc_folder_cached_size(p_folder_id BIGINT)
+RETURNS VOID AS $$
+DECLARE
+    v_folder_id BIGINT := p_folder_id;
+    v_parent_id BIGINT;
+BEGIN
+    WHILE v_folder_id IS NOT NULL LOOP
+        UPDATE folder f
+        SET cached_size =
+            COALESCE((
+                SELECT SUM(fi.file_size)
+                FROM "file" fi
+                WHERE fi.folder_id = f.folder_id
+                  AND fi.status = 'active'
+            ), 0)
+            +
+            COALESCE((
+                SELECT SUM(ch.cached_size)
+                FROM folder ch
+                WHERE ch.parent_folder_id = f.folder_id
+                  AND ch.status = 'active'
+            ), 0)
+        WHERE f.folder_id = v_folder_id;
+
+        SELECT parent_folder_id INTO v_parent_id
+        FROM folder
+        WHERE folder_id = v_folder_id;
+
+        v_folder_id := v_parent_id;
+    END LOOP;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION rebuild_all_folder_cached_size()
+RETURNS VOID AS $$
+DECLARE
+    r RECORD;
+BEGIN
+    FOR r IN
+        WITH RECURSIVE tree AS (
+            SELECT folder_id, parent_folder_id, 0 AS depth
+            FROM folder
+            WHERE parent_folder_id IS NULL
+
+            UNION ALL
+
+            SELECT f.folder_id, f.parent_folder_id, t.depth + 1
+            FROM folder f
+            JOIN tree t ON f.parent_folder_id = t.folder_id
+        )
+        SELECT folder_id
+        FROM tree
+        ORDER BY depth DESC, folder_id DESC
+    LOOP
+        PERFORM recalc_folder_cached_size(r.folder_id);
+    END LOOP;
+END;
+$$ LANGUAGE plpgsql;
+
+CREATE OR REPLACE FUNCTION check_folder_parent_valid()
+RETURNS TRIGGER AS $$
+DECLARE
+    v_parent_owner BIGINT;
+    v_parent_status folder_status_enum;
+    v_has_cycle BOOLEAN := FALSE;
+BEGIN
+    IF NEW.parent_folder_id IS NULL THEN
+        RETURN NEW;
+    END IF;
+
+    SELECT owner_id, status
+      INTO v_parent_owner, v_parent_status
+    FROM folder
+    WHERE folder_id = NEW.parent_folder_id;
+
+    IF NOT FOUND THEN
+        RAISE EXCEPTION 'Parent folder % does not exist', NEW.parent_folder_id;
+    END IF;
+
+    IF v_parent_owner <> NEW.owner_id THEN
+        RAISE EXCEPTION 'Parent folder owner must match folder owner';
+    END IF;
+
+    IF NEW.status = 'active' AND v_parent_status <> 'active' THEN
+        RAISE EXCEPTION 'Active folder cannot be placed under a non-active parent folder';
+    END IF;
+
+    IF NEW.folder_id IS NOT NULL THEN
+        IF NEW.parent_folder_id = NEW.folder_id THEN
+            RAISE EXCEPTION 'Folder cannot be its own parent';
+        END IF;
+
+        WITH RECURSIVE descendants AS (
+            SELECT folder_id
+            FROM folder
+            WHERE parent_folder_id = NEW.folder_id
+
+            UNION ALL
+
+            SELECT f.folder_id
+            FROM folder f
+            JOIN descendants d ON f.parent_folder_id = d.folder_id
+        )
+        SELECT EXISTS(
+            SELECT 1
+            FROM descendants
+            WHERE folder_id = NEW.parent_folder_id
+        )
+        INTO v_has_cycle;
+
+        IF v_has_cycle THEN
+            RAISE EXCEPTION 'Folder cannot be moved into its own descendant';
+        END IF;
+    END IF;
+
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_folder_validate ON folder;
+CREATE TRIGGER trg_folder_validate
+BEFORE INSERT OR UPDATE OF parent_folder_id, owner_id, status ON folder
+FOR EACH ROW
+EXECUTE FUNCTION check_folder_parent_valid();
+
+CREATE OR REPLACE FUNCTION check_file_folder_valid()
+RETURNS TRIGGER AS $$
+DECLARE
+    v_folder_owner BIGINT;
+    v_folder_status folder_status_enum;
+BEGIN
+    SELECT owner_id, status
+      INTO v_folder_owner, v_folder_status
+    FROM folder
+    WHERE folder_id = NEW.folder_id;
+
+    IF NOT FOUND THEN
+        RAISE EXCEPTION 'Folder % does not exist', NEW.folder_id;
+    END IF;
+
+    IF NEW.status = 'active' THEN
+        IF v_folder_owner <> NEW.owner_id THEN
+            RAISE EXCEPTION 'File owner must match folder owner';
+        END IF;
+
+        IF v_folder_status <> 'active' THEN
+            RAISE EXCEPTION 'Active file cannot be placed under a non-active folder';
+        END IF;
+    END IF;
+
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_file_validate ON "file";
+CREATE TRIGGER trg_file_validate
+BEFORE INSERT OR UPDATE OF folder_id, owner_id, status ON "file"
+FOR EACH ROW
+EXECUTE FUNCTION check_file_folder_valid();
+
+CREATE OR REPLACE FUNCTION sync_file_derived_fields()
+RETURNS TRIGGER AS $$
+BEGIN
+    IF TG_OP = 'INSERT' THEN
+        PERFORM recalc_storage_object_ref_count(NEW.storage_object_id);
+        PERFORM recalc_user_storage_used(NEW.owner_id);
+        PERFORM recalc_folder_cached_size(NEW.folder_id);
+        RETURN NULL;
+    ELSIF TG_OP = 'UPDATE' THEN
+        PERFORM recalc_storage_object_ref_count(OLD.storage_object_id);
+        IF NEW.storage_object_id IS DISTINCT FROM OLD.storage_object_id THEN
+            PERFORM recalc_storage_object_ref_count(NEW.storage_object_id);
+        END IF;
+
+        PERFORM recalc_user_storage_used(OLD.owner_id);
+        IF NEW.owner_id IS DISTINCT FROM OLD.owner_id THEN
+            PERFORM recalc_user_storage_used(NEW.owner_id);
+        END IF;
+
+        PERFORM recalc_folder_cached_size(OLD.folder_id);
+        IF NEW.folder_id IS DISTINCT FROM OLD.folder_id THEN
+            PERFORM recalc_folder_cached_size(NEW.folder_id);
+        END IF;
+        RETURN NULL;
+    ELSE
+        PERFORM recalc_storage_object_ref_count(OLD.storage_object_id);
+        PERFORM recalc_user_storage_used(OLD.owner_id);
+        PERFORM recalc_folder_cached_size(OLD.folder_id);
+        RETURN NULL;
+    END IF;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_file_sync_derived_fields ON "file";
+CREATE TRIGGER trg_file_sync_derived_fields
+AFTER INSERT OR UPDATE OR DELETE ON "file"
+FOR EACH ROW
+EXECUTE FUNCTION sync_file_derived_fields();
+
+CREATE OR REPLACE FUNCTION sync_folder_cached_size()
+RETURNS TRIGGER AS $$
+BEGIN
+    IF TG_OP = 'INSERT' THEN
+        PERFORM recalc_folder_cached_size(NEW.folder_id);
+        PERFORM recalc_folder_cached_size(NEW.parent_folder_id);
+        RETURN NULL;
+    ELSIF TG_OP = 'UPDATE' THEN
+        PERFORM recalc_folder_cached_size(OLD.parent_folder_id);
+        PERFORM recalc_folder_cached_size(NEW.folder_id);
+        IF NEW.parent_folder_id IS DISTINCT FROM OLD.parent_folder_id THEN
+            PERFORM recalc_folder_cached_size(NEW.parent_folder_id);
+        END IF;
+        RETURN NULL;
+    ELSE
+        PERFORM recalc_folder_cached_size(OLD.parent_folder_id);
+        RETURN NULL;
+    END IF;
+END;
+$$ LANGUAGE plpgsql;
+
+DROP TRIGGER IF EXISTS trg_folder_sync_cached_size ON folder;
+CREATE TRIGGER trg_folder_sync_cached_size
+AFTER INSERT OR DELETE OR UPDATE OF parent_folder_id, status ON folder
+FOR EACH ROW
+EXECUTE FUNCTION sync_folder_cached_size();
+
+UPDATE storage_object so
+SET ref_count = x.ref_count
+FROM (
+    SELECT storage_object_id, COUNT(*) AS ref_count
+    FROM "file"
+    WHERE status = 'active'
+    GROUP BY storage_object_id
+) x
+WHERE so.object_id = x.storage_object_id;
+
+UPDATE storage_object so
+SET ref_count = 0
+WHERE NOT EXISTS (
+    SELECT 1
+    FROM "file" f
+    WHERE f.storage_object_id = so.object_id
+      AND f.status = 'active'
+);
+
+UPDATE "user" u
+SET storage_used = x.total_size
+FROM (
+    SELECT owner_id AS user_id, COALESCE(SUM(file_size), 0) AS total_size
+    FROM "file"
+    WHERE status = 'active'
+    GROUP BY owner_id
+) x
+WHERE u.user_id = x.user_id;
+
+UPDATE "user" u
+SET storage_used = 0
+WHERE NOT EXISTS (
+    SELECT 1
+    FROM "file" f
+    WHERE f.owner_id = u.user_id
+      AND f.status = 'active'
+);
+
+SELECT rebuild_all_folder_cached_size();
+
+DROP VIEW IF EXISTS v_shared_with_me;
+DROP VIEW IF EXISTS v_user_permissions;
+DROP VIEW IF EXISTS v_user_recycle_bin;
+DROP VIEW IF EXISTS v_full_path;
+DROP VIEW IF EXISTS v_file_folder_details;
+DROP VIEW IF EXISTS v_user_storage_summary;
+DROP VIEW IF EXISTS v_admin_share_overview;
+DROP VIEW IF EXISTS v_user_dashboard;
+
+CREATE VIEW v_file_folder_details AS
+SELECT
+    'file' AS item_type,
+    f.file_id AS id,
+    f.file_name AS name,
+    f.file_size AS size,
+    f.mime_type,
+    f.folder_id AS parent_id,
+    f.owner_id,
+    u.username AS owner_name,
+    f.created_at,
+    f.updated_at
+FROM "file" f
+JOIN "user" u ON f.owner_id = u.user_id
+JOIN storage_object so ON f.storage_object_id = so.object_id
+WHERE f.status = 'active'
+  AND so.upload_status = 'active'
+
+UNION ALL
+
+SELECT
+    'folder' AS item_type,
+    fo.folder_id AS id,
+    fo.folder_name AS name,
+    fo.cached_size AS size,
+    'inode/directory' AS mime_type,
+    fo.parent_folder_id AS parent_id,
+    fo.owner_id,
+    u.username AS owner_name,
+    fo.created_at,
+    fo.updated_at
+FROM folder fo
+JOIN "user" u ON fo.owner_id = u.user_id
+WHERE fo.status = 'active';
+
+CREATE VIEW v_user_permissions AS
+SELECT
+    acl.id AS acl_id,
+    u.user_id,
+    u.username AS user_name,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    CASE WHEN acl.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    acl.permission_role,
+    acl.can_preview,
+    acl.can_download,
+    acl.can_save,
+    acl.can_share,
+    acl.expire_at,
+    'direct'::TEXT AS grant_source
+FROM acl
+JOIN "user" u ON acl.user_id = u.user_id
+LEFT JOIN "file" f ON acl.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON acl.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE acl.user_id IS NOT NULL
+  AND (
+      (acl.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (acl.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  )
+
+UNION ALL
+
+SELECT
+    acl.id AS acl_id,
+    u.user_id,
+    u.username AS user_name,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    CASE WHEN acl.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    acl.permission_role,
+    acl.can_preview,
+    acl.can_download,
+    acl.can_save,
+    acl.can_share,
+    acl.expire_at,
+    'group'::TEXT AS grant_source
+FROM acl
+JOIN user_group_member ugm ON acl.group_id = ugm.group_id
+JOIN "user" u ON ugm.user_id = u.user_id
+LEFT JOIN "file" f ON acl.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON acl.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE acl.group_id IS NOT NULL
+  AND (
+      (acl.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (acl.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  );
+
+CREATE VIEW v_user_storage_summary AS
+SELECT
+    user_id,
+    username,
+    status,
+    storage_limit,
+    storage_used,
+    CASE
+        WHEN storage_limit <= 0 THEN 0::NUMERIC(10,2)
+        ELSE ROUND((storage_used::NUMERIC / storage_limit::NUMERIC) * 100, 2)
+    END AS storage_used_pct
+FROM "user";
+
+CREATE VIEW v_shared_with_me AS
+SELECT
+    s.share_id,
+    CASE WHEN s.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    owner.user_id AS shared_by_user_id,
+    owner.username AS shared_by,
+    sm.user_id AS shared_to_user_id,
+    sm.status AS member_status,
+    s.share_type,
+    s.permission_role,
+    s.allow_preview,
+    s.allow_download,
+    s.allow_save,
+    s.allow_reshare,
+    sm.target_folder_id,
+    sm.accepted_at,
+    s.expire_time,
+    s.created_at AS shared_at
+FROM share s
+JOIN share_member sm ON s.share_id = sm.share_id
+JOIN "user" owner ON s.user_id = owner.user_id
+LEFT JOIN "file" f ON s.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON s.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE sm.user_id IS NOT NULL
+  AND sm.status IN ('pending', 'accepted')
+  AND s.status = 'active'
+  AND (s.expire_time IS NULL OR s.expire_time > CURRENT_TIMESTAMP)
+  AND (
+      (s.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (s.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  )
+
+UNION ALL
+
+SELECT
+    s.share_id,
+    CASE WHEN s.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    owner.user_id AS shared_by_user_id,
+    owner.username AS shared_by,
+    ugm.user_id AS shared_to_user_id,
+    sm.status AS member_status,
+    s.share_type,
+    s.permission_role,
+    s.allow_preview,
+    s.allow_download,
+    s.allow_save,
+    s.allow_reshare,
+    sm.target_folder_id,
+    sm.accepted_at,
+    s.expire_time,
+    s.created_at AS shared_at
+FROM share s
+JOIN share_member sm ON s.share_id = sm.share_id
+JOIN user_group_member ugm ON sm.group_id = ugm.group_id
+JOIN "user" owner ON s.user_id = owner.user_id
+LEFT JOIN "file" f ON s.file_id = f.file_id AND f.status = 'active'
+LEFT JOIN folder fo ON s.folder_id = fo.folder_id AND fo.status = 'active'
+WHERE sm.group_id IS NOT NULL
+  AND sm.status IN ('pending', 'accepted')
+  AND s.status = 'active'
+  AND (s.expire_time IS NULL OR s.expire_time > CURRENT_TIMESTAMP)
+  AND (
+      (s.file_id IS NOT NULL AND f.file_id IS NOT NULL)
+      OR
+      (s.folder_id IS NOT NULL AND fo.folder_id IS NOT NULL)
+  );
+
+CREATE VIEW v_full_path AS
+WITH RECURSIVE folder_path AS (
+    SELECT
+        folder_id,
+        owner_id,
+        parent_folder_id,
+        folder_name,
+        CAST(folder_name AS VARCHAR(2048)) AS path
+    FROM folder
+    WHERE parent_folder_id IS NULL
+      AND status = 'active'
+
+    UNION ALL
+
+    SELECT
+        f.folder_id,
+        f.owner_id,
+        f.parent_folder_id,
+        f.folder_name,
+        fp.path || '/' || f.folder_name AS path
+    FROM folder f
+    JOIN folder_path fp
+      ON f.parent_folder_id = fp.folder_id
+     AND f.owner_id = fp.owner_id
+    WHERE f.status = 'active'
+)
+SELECT
+    folder_id AS id,
+    owner_id,
+    parent_folder_id,
+    path
+FROM folder_path;
+
+CREATE VIEW v_user_recycle_bin AS
+SELECT
+    'file' AS item_type,
+    f.file_id AS id,
+    f.file_name AS name,
+    f.file_size AS size,
+    f.folder_id AS parent_id,
+    f.owner_id,
+    u.username AS owner_name,
+    f.deleted_at
+FROM "file" f
+JOIN "user" u ON f.owner_id = u.user_id
+WHERE f.status = 'deleted'
+  AND f.deleted_at IS NOT NULL
+
+UNION ALL
+
+SELECT
+    'folder' AS item_type,
+    fo.folder_id AS id,
+    fo.folder_name AS name,
+    fo.cached_size AS size,
+    fo.parent_folder_id AS parent_id,
+    fo.owner_id,
+    u.username AS owner_name,
+    fo.deleted_at
+FROM folder fo
+JOIN "user" u ON fo.owner_id = u.user_id
+WHERE fo.status = 'deleted'
+  AND fo.deleted_at IS NOT NULL;
+
+CREATE VIEW v_admin_share_overview AS
+SELECT
+    s.share_id,
+    s.share_code,
+    s.status,
+    s.share_type,
+    s.user_id AS created_by_user_id,
+    u.username AS created_by,
+    CASE WHEN s.file_id IS NOT NULL THEN 'file' ELSE 'folder' END AS item_type,
+    COALESCE(f.file_id, fo.folder_id) AS item_id,
+    COALESCE(f.file_name, fo.folder_name) AS item_name,
+    s.permission_role,
+    s.allow_preview,
+    s.allow_download,
+    s.allow_save,
+    s.allow_reshare,
+    s.require_login,
+    s.password_hash IS NOT NULL AS has_password,
+    s.expire_time,
+    s.visit_count,
+    s.download_count,
+    s.created_at,
+    s.updated_at
+FROM share s
+JOIN "user" u ON s.user_id = u.user_id
+LEFT JOIN "file" f ON s.file_id = f.file_id
+LEFT JOIN folder fo ON s.folder_id = fo.folder_id;
+
+CREATE VIEW v_user_dashboard AS
+SELECT
+    u.user_id,
+    u.username,
+    u.email,
+    u.status,
+    u.storage_limit,
+    u.storage_used,
+    CASE
+        WHEN u.storage_limit <= 0 THEN 0::NUMERIC(10,2)
+        ELSE ROUND((u.storage_used::NUMERIC / u.storage_limit::NUMERIC) * 100, 2)
+    END AS storage_used_pct,
+    COALESCE(f.file_count, 0) AS active_file_count,
+    COALESCE(fo.folder_count, 0) AS active_folder_count,
+    COALESCE(s.active_share_count, 0) AS active_share_count,
+    COALESCE(fv.favorite_count, 0) AS favorite_count,
+    u.last_login_at,
+    u.created_at
+FROM "user" u
+LEFT JOIN (
+    SELECT owner_id, COUNT(*) AS file_count
+    FROM "file"
+    WHERE status = 'active'
+    GROUP BY owner_id
+) f ON u.user_id = f.owner_id
+LEFT JOIN (
+    SELECT owner_id, COUNT(*) AS folder_count
+    FROM folder
+    WHERE status = 'active'
+    GROUP BY owner_id
+) fo ON u.user_id = fo.owner_id
+LEFT JOIN (
+    SELECT user_id, COUNT(*) AS active_share_count
+    FROM share
+    WHERE status = 'active'
+      AND (expire_time IS NULL OR expire_time > CURRENT_TIMESTAMP)
+    GROUP BY user_id
+) s ON u.user_id = s.user_id
+LEFT JOIN (
+    SELECT user_id, COUNT(*) AS favorite_count
+    FROM favorite_item
+    GROUP BY user_id
+) fv ON u.user_id = fv.user_id;
diff --git a/docs/sql/postgres/90_comments.sql b/docs/sql/postgres/90_comments.sql
new file mode 100644
index 0000000..b28721e
--- /dev/null
+++ b/docs/sql/postgres/90_comments.sql
@@ -0,0 +1,248 @@
+-- =========================
+-- Comments: table and column descriptions
+-- =========================
+
+COMMENT ON TABLE "user" IS '用户账户主表';
+COMMENT ON COLUMN "user".user_id IS '用户主键';
+COMMENT ON COLUMN "user".username IS '用户名（全局大小写不敏感唯一）';
+COMMENT ON COLUMN "user".email IS '邮箱（全局大小写不敏感唯一）';
+COMMENT ON COLUMN "user".password_hash IS '密码哈希';
+COMMENT ON COLUMN "user".role IS '平台角色，例如 USER/ADMIN';
+COMMENT ON COLUMN "user".status IS '账号状态';
+COMMENT ON COLUMN "user".email_verified IS '邮箱是否已验证';
+COMMENT ON COLUMN "user".storage_limit IS '存储配额（字节）';
+COMMENT ON COLUMN "user".storage_used IS '已用空间（字节）';
+COMMENT ON COLUMN "user".failed_login_count IS '连续登录失败次数';
+COMMENT ON COLUMN "user".locked_until IS '账号锁定截止时间';
+
+COMMENT ON TABLE user_group IS '用户组定义';
+COMMENT ON COLUMN user_group.id IS '用户组主键';
+COMMENT ON COLUMN user_group.name IS '用户组名称';
+COMMENT ON COLUMN user_group.description IS '用户组说明';
+
+COMMENT ON TABLE user_group_member IS '用户组成员关系';
+COMMENT ON COLUMN user_group_member.id IS '成员关系主键';
+COMMENT ON COLUMN user_group_member.user_id IS '用户ID';
+COMMENT ON COLUMN user_group_member.group_id IS '用户组ID';
+COMMENT ON COLUMN user_group_member.role IS '组内角色';
+
+COMMENT ON TABLE storage_object IS '物理存储对象（对象存储层）';
+COMMENT ON COLUMN storage_object.object_id IS '对象主键';
+COMMENT ON COLUMN storage_object.object_hash IS '对象内容哈希';
+COMMENT ON COLUMN storage_object.hash_algorithm IS '哈希算法';
+COMMENT ON COLUMN storage_object.bucket_name IS '对象存储桶名';
+COMMENT ON COLUMN storage_object.object_key IS '对象存储键';
+COMMENT ON COLUMN storage_object.object_size IS '对象大小（字节）';
+COMMENT ON COLUMN storage_object.upload_status IS '上传与可用状态';
+COMMENT ON COLUMN storage_object.scan_status IS '安全扫描状态';
+COMMENT ON COLUMN storage_object.moderation_status IS '内容审核状态';
+COMMENT ON COLUMN storage_object.ref_count IS '被逻辑文件引用计数';
+
+COMMENT ON TABLE folder IS '文件夹目录节点';
+COMMENT ON COLUMN folder.folder_id IS '目录主键';
+COMMENT ON COLUMN folder.owner_id IS '目录所有者用户ID';
+COMMENT ON COLUMN folder.parent_folder_id IS '父目录ID，根目录为NULL';
+COMMENT ON COLUMN folder.folder_name IS '目录名';
+COMMENT ON COLUMN folder.cached_size IS '缓存目录大小（字节）';
+COMMENT ON COLUMN folder.status IS '目录状态';
+COMMENT ON COLUMN folder.folder_type IS '目录类型（normal/root/system）';
+COMMENT ON COLUMN folder.deleted_by IS '删除操作者用户ID';
+
+COMMENT ON TABLE "file" IS '逻辑文件记录';
+COMMENT ON COLUMN "file".file_id IS '文件主键';
+COMMENT ON COLUMN "file".uploader_id IS '上传者用户ID';
+COMMENT ON COLUMN "file".owner_id IS '文件所有者用户ID';
+COMMENT ON COLUMN "file".folder_id IS '所在目录ID';
+COMMENT ON COLUMN "file".file_name IS '文件名';
+COMMENT ON COLUMN "file".mime_type IS 'MIME 类型';
+COMMENT ON COLUMN "file".storage_object_id IS '关联物理对象ID';
+COMMENT ON COLUMN "file".file_size IS '文件大小（字节）';
+COMMENT ON COLUMN "file".status IS '文件状态';
+COMMENT ON COLUMN "file".last_accessed_at IS '最后访问时间';
+
+COMMENT ON TABLE acl IS '访问控制列表（文件/目录授权）';
+COMMENT ON COLUMN acl.id IS 'ACL主键';
+COMMENT ON COLUMN acl.file_id IS '授权文件ID';
+COMMENT ON COLUMN acl.folder_id IS '授权目录ID';
+COMMENT ON COLUMN acl.user_id IS '被授权用户ID';
+COMMENT ON COLUMN acl.group_id IS '被授权用户组ID';
+COMMENT ON COLUMN acl.permission_role IS '权限角色 viewer/editor/manager';
+COMMENT ON COLUMN acl.can_preview IS '是否允许预览';
+COMMENT ON COLUMN acl.can_download IS '是否允许下载';
+COMMENT ON COLUMN acl.can_save IS '是否允许保存到我的网盘';
+COMMENT ON COLUMN acl.can_share IS '是否允许继续分享';
+COMMENT ON COLUMN acl.expire_at IS '授权过期时间';
+
+COMMENT ON TABLE share IS '分享链接与分享策略';
+COMMENT ON COLUMN share.share_id IS '分享主键';
+COMMENT ON COLUMN share.user_id IS '分享发起人用户ID';
+COMMENT ON COLUMN share.file_id IS '被分享文件ID';
+COMMENT ON COLUMN share.folder_id IS '被分享目录ID';
+COMMENT ON COLUMN share.share_link IS '兼容旧版的分享链接';
+COMMENT ON COLUMN share.share_code IS '短分享码';
+COMMENT ON COLUMN share.status IS '分享状态';
+COMMENT ON COLUMN share.permission_role IS '分享默认权限角色';
+COMMENT ON COLUMN share.allow_download IS '是否允许下载';
+COMMENT ON COLUMN share.allow_save IS '是否允许保存到我的网盘';
+COMMENT ON COLUMN share.require_login IS '访问是否要求登录';
+COMMENT ON COLUMN share.expire_time IS '分享过期时间';
+COMMENT ON COLUMN share.visit_count IS '访问次数';
+COMMENT ON COLUMN share.download_count IS '下载次数';
+
+COMMENT ON TABLE share_member IS '定向分享成员（用户或用户组）';
+COMMENT ON COLUMN share_member.id IS '分享成员主键';
+COMMENT ON COLUMN share_member.share_id IS '关联分享ID';
+COMMENT ON COLUMN share_member.user_id IS '被分享用户ID';
+COMMENT ON COLUMN share_member.group_id IS '被分享用户组ID';
+COMMENT ON COLUMN share_member.status IS '接受状态';
+COMMENT ON COLUMN share_member.target_folder_id IS '接受后落地目录ID';
+COMMENT ON COLUMN share_member.accepted_at IS '接受时间';
+
+COMMENT ON TABLE favorite_item IS '用户星标项';
+COMMENT ON COLUMN favorite_item.favorite_id IS '星标主键';
+COMMENT ON COLUMN favorite_item.user_id IS '用户ID';
+COMMENT ON COLUMN favorite_item.item_type IS '星标项类型 file/folder';
+COMMENT ON COLUMN favorite_item.file_id IS '星标文件ID';
+COMMENT ON COLUMN favorite_item.folder_id IS '星标目录ID';
+
+COMMENT ON TABLE user_folder_preference IS '用户目录视图偏好';
+COMMENT ON COLUMN user_folder_preference.preference_id IS '偏好主键';
+COMMENT ON COLUMN user_folder_preference.user_id IS '用户ID';
+COMMENT ON COLUMN user_folder_preference.folder_id IS '目录ID，NULL表示全局默认';
+COMMENT ON COLUMN user_folder_preference.view_mode IS '展示模式 list/grid';
+COMMENT ON COLUMN user_folder_preference.sort_by IS '排序字段';
+COMMENT ON COLUMN user_folder_preference.sort_direction IS '排序方向';
+
+COMMENT ON TABLE "log" IS '审计日志';
+COMMENT ON COLUMN "log".id IS '日志主键';
+COMMENT ON COLUMN "log".user_id IS '操作用户ID（可为空）';
+COMMENT ON COLUMN "log".actor_type IS '行为主体类型';
+COMMENT ON COLUMN "log".operation IS '操作类型';
+COMMENT ON COLUMN "log".target_type IS '目标资源类型';
+COMMENT ON COLUMN "log".target_id IS '目标资源ID';
+COMMENT ON COLUMN "log".result IS '操作结果';
+COMMENT ON COLUMN "log".request_id IS '请求链路ID';
+
+COMMENT ON TABLE notification IS '站内通知';
+COMMENT ON COLUMN notification.id IS '通知主键';
+COMMENT ON COLUMN notification.user_id IS '接收用户ID';
+COMMENT ON COLUMN notification.type IS '通知业务类型';
+COMMENT ON COLUMN notification.channel IS '发送渠道';
+COMMENT ON COLUMN notification.message IS '通知正文';
+COMMENT ON COLUMN notification.payload IS '扩展载荷(JSON)';
+COMMENT ON COLUMN notification.is_read IS '是否已读';
+COMMENT ON COLUMN notification.read_at IS '已读时间';
+COMMENT ON COLUMN notification.sender_user_id IS '发送方用户ID';
+
+COMMENT ON TABLE upload_task IS '上传任务';
+COMMENT ON COLUMN upload_task.task_id IS '上传任务主键';
+COMMENT ON COLUMN upload_task.user_id IS '任务所属用户ID';
+COMMENT ON COLUMN upload_task.folder_id IS '目标目录ID';
+COMMENT ON COLUMN upload_task.file_name IS '客户端文件名';
+COMMENT ON COLUMN upload_task.total_size IS '文件总大小（字节）';
+COMMENT ON COLUMN upload_task.chunk_size IS '分片大小（字节）';
+COMMENT ON COLUMN upload_task.uploaded_bytes IS '已上传字节数';
+COMMENT ON COLUMN upload_task.client_file_id IS '客户端幂等ID';
+COMMENT ON COLUMN upload_task.status IS '上传任务状态';
+COMMENT ON COLUMN upload_task.upload_id IS '多段上传会话ID';
+
+COMMENT ON TABLE upload_task_part IS '上传任务分片';
+COMMENT ON COLUMN upload_task_part.id IS '分片主键';
+COMMENT ON COLUMN upload_task_part.task_id IS '上传任务ID';
+COMMENT ON COLUMN upload_task_part.part_number IS '分片序号';
+COMMENT ON COLUMN upload_task_part.part_size IS '分片大小（字节）';
+COMMENT ON COLUMN upload_task_part.status IS '分片状态';
+COMMENT ON COLUMN upload_task_part.checksum IS '分片校验值';
+COMMENT ON COLUMN upload_task_part.retry_count IS '分片重试次数';
+
+COMMENT ON TABLE password_reset_token IS '密码重置令牌';
+COMMENT ON COLUMN password_reset_token.token_id IS '令牌主键';
+COMMENT ON COLUMN password_reset_token.user_id IS '用户ID';
+COMMENT ON COLUMN password_reset_token.token_hash IS '令牌哈希';
+COMMENT ON COLUMN password_reset_token.expire_at IS '过期时间';
+COMMENT ON COLUMN password_reset_token.used_at IS '使用时间';
+
+COMMENT ON TABLE email_verification_token IS '邮箱验证令牌';
+COMMENT ON COLUMN email_verification_token.token_id IS '令牌主键';
+COMMENT ON COLUMN email_verification_token.user_id IS '用户ID';
+COMMENT ON COLUMN email_verification_token.token_hash IS '令牌哈希';
+COMMENT ON COLUMN email_verification_token.expire_at IS '过期时间';
+COMMENT ON COLUMN email_verification_token.verified_at IS '验证完成时间';
+
+COMMENT ON TABLE user_session IS '用户会话与刷新令牌';
+COMMENT ON COLUMN user_session.session_id IS '会话主键';
+COMMENT ON COLUMN user_session.user_id IS '用户ID';
+COMMENT ON COLUMN user_session.refresh_token_hash IS '刷新令牌哈希';
+COMMENT ON COLUMN user_session.client_type IS '客户端类型';
+COMMENT ON COLUMN user_session.device_id IS '设备ID';
+COMMENT ON COLUMN user_session.last_seen_at IS '最近活跃时间';
+COMMENT ON COLUMN user_session.expire_at IS '会话过期时间';
+COMMENT ON COLUMN user_session.revoked_at IS '会话吊销时间';
+
+COMMENT ON TABLE file_preview_asset IS '文件预览产物';
+COMMENT ON COLUMN file_preview_asset.preview_id IS '预览产物主键';
+COMMENT ON COLUMN file_preview_asset.source_object_id IS '源对象ID';
+COMMENT ON COLUMN file_preview_asset.preview_object_id IS '预览对象ID';
+COMMENT ON COLUMN file_preview_asset.preview_type IS '预览类型';
+COMMENT ON COLUMN file_preview_asset.page_no IS '页码（文档类）';
+COMMENT ON COLUMN file_preview_asset.status IS '预览生成状态';
+
+COMMENT ON TABLE file_media_metadata IS '媒体元数据';
+COMMENT ON COLUMN file_media_metadata.metadata_id IS '媒体元数据主键';
+COMMENT ON COLUMN file_media_metadata.source_object_id IS '源对象ID';
+COMMENT ON COLUMN file_media_metadata.width IS '媒体宽度';
+COMMENT ON COLUMN file_media_metadata.height IS '媒体高度';
+COMMENT ON COLUMN file_media_metadata.duration_ms IS '时长（毫秒）';
+COMMENT ON COLUMN file_media_metadata.extra_metadata IS '扩展元数据(JSON)';
+
+COMMENT ON TABLE object_scan_result IS '对象扫描结果';
+COMMENT ON COLUMN object_scan_result.scan_id IS '扫描记录主键';
+COMMENT ON COLUMN object_scan_result.object_id IS '对象ID';
+COMMENT ON COLUMN object_scan_result.scan_type IS '扫描类型';
+COMMENT ON COLUMN object_scan_result.engine_name IS '扫描引擎名称';
+COMMENT ON COLUMN object_scan_result.result IS '扫描结果';
+COMMENT ON COLUMN object_scan_result.details IS '扫描明细(JSON)';
+
+COMMENT ON TABLE moderation_case IS '内容审核工单';
+COMMENT ON COLUMN moderation_case.case_id IS '工单主键';
+COMMENT ON COLUMN moderation_case.object_id IS '对象ID';
+COMMENT ON COLUMN moderation_case.file_id IS '关联文件ID';
+COMMENT ON COLUMN moderation_case.reason_type IS '触发原因类型';
+COMMENT ON COLUMN moderation_case.confidence IS '置信度';
+COMMENT ON COLUMN moderation_case.status IS '工单状态';
+COMMENT ON COLUMN moderation_case.resolution IS '处置结果';
+
+COMMENT ON TABLE security_event IS '安全事件';
+COMMENT ON COLUMN security_event.event_id IS '安全事件主键';
+COMMENT ON COLUMN security_event.user_id IS '关联用户ID';
+COMMENT ON COLUMN security_event.session_id IS '关联会话ID';
+COMMENT ON COLUMN security_event.event_type IS '事件类型';
+COMMENT ON COLUMN security_event.severity IS '风险级别';
+COMMENT ON COLUMN security_event.occurred_at IS '事件发生时间';
+
+COMMENT ON TABLE batch_download_task IS '批量下载打包任务';
+COMMENT ON COLUMN batch_download_task.task_id IS '任务主键';
+COMMENT ON COLUMN batch_download_task.user_id IS '用户ID';
+COMMENT ON COLUMN batch_download_task.archive_name IS '压缩包文件名';
+COMMENT ON COLUMN batch_download_task.item_count IS '打包条目数';
+COMMENT ON COLUMN batch_download_task.items IS '打包条目清单(JSON)';
+COMMENT ON COLUMN batch_download_task.status IS '任务状态';
+COMMENT ON COLUMN batch_download_task.storage_object_id IS '生成压缩包对象ID';
+COMMENT ON COLUMN batch_download_task.completed_at IS '完成时间';
+
+COMMENT ON TABLE share_access_log IS '分享访问日志';
+COMMENT ON COLUMN share_access_log.id IS '访问日志主键';
+COMMENT ON COLUMN share_access_log.share_id IS '分享ID';
+COMMENT ON COLUMN share_access_log.user_id IS '访问用户ID';
+COMMENT ON COLUMN share_access_log.event_type IS '事件类型（visit/download）';
+COMMENT ON COLUMN share_access_log.result IS '事件结果';
+COMMENT ON COLUMN share_access_log.created_at IS '事件发生时间';
+
+COMMENT ON VIEW v_file_folder_details IS '文件与目录统一列表视图';
+COMMENT ON VIEW v_user_permissions IS '用户有效权限视图（直授+组授）';
+COMMENT ON VIEW v_user_storage_summary IS '用户空间使用汇总视图';
+COMMENT ON VIEW v_shared_with_me IS '共享给我的资源视图';
+COMMENT ON VIEW v_full_path IS '目录全路径视图';
+COMMENT ON VIEW v_user_recycle_bin IS '用户回收站视图';
+COMMENT ON VIEW v_admin_share_overview IS '管理员分享总览视图';
+COMMENT ON VIEW v_user_dashboard IS '管理员用户仪表盘视图';