From ae6ba75557cdc2b8a778d8f1587b65ed2b1bb105 Mon Sep 17 00:00:00 2001
From: prql-bot <107324867+prql-bot@users.noreply.github.com>
Date: Thu, 13 Aug 2026 06:58:43 +0000
Subject: [PATCH 1/2] internal: remove dead code from the SQL backend

---
 prqlc/prqlc/src/sql/dialect.rs   |  9 --------
 prqlc/prqlc/src/sql/gen_query.rs | 37 ++++----------------------------
 2 files changed, 4 insertions(+), 42 deletions(-)

diff --git a/prqlc/prqlc/src/sql/dialect.rs b/prqlc/prqlc/src/sql/dialect.rs
index 9864b8d8b5a8..feb02a1a9feb 100644
--- a/prqlc/prqlc/src/sql/dialect.rs
+++ b/prqlc/prqlc/src/sql/dialect.rs
@@ -362,11 +362,6 @@ impl DialectHandler for PostgresDialect {
 }
 
 impl DialectHandler for RedshiftDialect {
-    fn ident_quoting_style(&self) -> IdentQuotingStyle {
-        // Use conditional quoting with dialect-specific keywords
-        IdentQuotingStyle::ConditionallyQuoted
-    }
-
     fn interval_quoting_style(&self, dtf: &DateTimeField) -> IntervalQuotingStyle {
         if matches!(dtf, DateTimeField::Week(_) | DateTimeField::Weeks) {
             IntervalQuotingStyle::ValueAndUnitQuoted
@@ -375,10 +370,6 @@ impl DialectHandler for RedshiftDialect {
         }
     }
 
-    fn supports_distinct_on(&self) -> bool {
-        false
-    }
-
     // https://docs.aws.amazon.com/redshift/latest/dg/r_FORMAT_strings.html
     fn translate_chrono_item(&self, item: Item) -> Result<String> {
         Ok(match item {
diff --git a/prqlc/prqlc/src/sql/gen_query.rs b/prqlc/prqlc/src/sql/gen_query.rs
index cbd0589e77ee..f17188d352c9 100644
--- a/prqlc/prqlc/src/sql/gen_query.rs
+++ b/prqlc/prqlc/src/sql/gen_query.rs
@@ -347,8 +347,7 @@ fn translate_set_ops_pipeline(
 }
 
 fn translate_relation_expr(relation_expr: RelationExpr, ctx: &mut Context) -> Result<TableFactor> {
-    let alias = Some(&relation_expr.riid)
-        .and_then(|riid| ctx.anchor.relation_instances.get(riid))
+    let alias = (ctx.anchor.relation_instances.get(&relation_expr.riid))
         .and_then(|ri| ri.table_ref.name.clone());
 
     Ok(match relation_expr.kind {
@@ -448,40 +447,12 @@ fn translate_cte(cte: Cte, ctx: &mut Context) -> Result<(sql_ast::Cte, bool)> {
                 right: step,
             });
 
-            (inner_query, true)
-
             // RECURSIVE can only follow WITH directly.
             // Initial implementation assumed that it applies only to the first CTE.
             // This meant that it had to wrap any-non-first CTE into a *nested* WITH, so the inner
-            // WITH could be RECURSIVE.
-            // This is implementation of that, in case some dialect requires it.
-            // let inner_cte = sql_ast::Cte {
-            //     alias: simple_table_alias(cte_name.clone()),
-            //     query: Box::new(inner_query),
-            //     from: None,
-            // };
-            // let outer_query = sql_ast::Query {
-            //     with: Some(sql_ast::With {
-            //         recursive: true,
-            //         cte_tables: vec![inner_cte],
-            //     }),
-            //     ..default_query(sql_ast::SetExpr::Select(Box::new(sql_ast::Select {
-            //         projection: vec![SelectItem::Wildcard(
-            //             sql_ast::WildcardAdditionalOptions::default(),
-            //         )],
-            //         from: vec![TableWithJoins {
-            //             relation: TableFactor::Table {
-            //                 name: sql_ast::ObjectName(vec![cte_name.clone()]),
-            //                 alias: None,
-            //                 args: None,
-            //                 with_hints: Vec::new(),
-            //             },
-            //             joins: vec![],
-            //         }],
-            //         ..default_select()
-            //     })))
-            // };
-            // (outer_query, false)
+            // WITH could be RECURSIVE. If a dialect ever needs that, the removed implementation is
+            // in the history of this file.
+            (inner_query, true)
         }
     };
 

From 87853d900e9b82a7863301b0609b55ca7c465a39 Mon Sep 17 00:00:00 2001
From: prql-bot <107324867+prql-bot@users.noreply.github.com>
Date: Thu, 13 Aug 2026 07:10:16 +0000
Subject: [PATCH 2/2] internal: cite the PR number in the recursive-CTE pointer

---
 prqlc/prqlc/src/sql/gen_query.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/prqlc/prqlc/src/sql/gen_query.rs b/prqlc/prqlc/src/sql/gen_query.rs
index f17188d352c9..608979c249c3 100644
--- a/prqlc/prqlc/src/sql/gen_query.rs
+++ b/prqlc/prqlc/src/sql/gen_query.rs
@@ -451,7 +451,7 @@ fn translate_cte(cte: Cte, ctx: &mut Context) -> Result<(sql_ast::Cte, bool)> {
             // Initial implementation assumed that it applies only to the first CTE.
             // This meant that it had to wrap any-non-first CTE into a *nested* WITH, so the inner
             // WITH could be RECURSIVE. If a dialect ever needs that, the removed implementation is
-            // in the history of this file.
+            // in the history of this file (deleted in #6190).
             (inner_query, true)
         }
     };