Schema lookup implementation

foundation_sql/cache.py

@@ -1,83 +1,84 @@
 import os
 from typing import Optional
 
+
 class SQLTemplateCache:
     """
     Simple file-based cache using file names as keys.
-    
+
     Attributes:
         cache_dir (str): Directory to store cached templates
     """
-    
+
     def __init__(self, cache_dir: str):
         """
         Initialize the SQL template cache.
-        
+
         Args:
             cache_dir (str): Directory to store cached templates
         """
         self.cache_dir = cache_dir
         os.makedirs(cache_dir, exist_ok=True)
-    
+
     def _get_cache_path(self, key: str) -> str:
         """
         Get the full path for a cache file.
-        
+
         Args:
             key (str): File name to use as cache key
-        
+
         Returns:
             str: Full path to the cache file
         """
         return os.path.join(self.cache_dir, key)
-    
+
     def set(self, key: str, template: str) -> None:
         """
         Store an SQL template in the cache.
-        
+
         Args:
             key (str): File name to use as cache key
             template (str): SQL template to cache
         """
         cache_file = self._get_cache_path(key)
-        with open(cache_file, 'w') as f:
+        with open(cache_file, "w") as f:
             f.write(template)
-    
+
     def get(self, key: str) -> Optional[str]:
         """
         Retrieve a cached SQL template.
-        
+
         Args:
             key (str): File name to use as cache key
-        
+
         Returns:
             Optional[str]: Cached SQL template or None if not found
         """
         cache_file = self._get_cache_path(key)
         if os.path.exists(cache_file):
-            with open(cache_file, 'r') as f:
+            with open(cache_file, "r") as f:
                 return f.read()
         return None
-    
+
     def exists(self, key: str) -> bool:
         """
         Check if a cache entry exists.
-        
+
         Args:
             key (str): File name to use as cache key
-        
+
         Returns:
             bool: True if cache entry exists, False otherwise
         """
         cache_file = self._get_cache_path(key)
         return os.path.exists(cache_file)
-    
+
     def clear(self, key: Optional[str] = None) -> None:
         """
         Clear cached templates.
-        
+
         Args:
-            key (Optional[str]): Specific key to clear. 
+            key (Optional[str]): Specific key to clear.
                                  If None, clears entire cache.
         """
         if key: