diff --git a/backend/app/__pycache__/main.cpython-312.pyc b/backend/app/__pycache__/main.cpython-312.pyc
index a1fc247..39d396a 100644
Binary files a/backend/app/__pycache__/main.cpython-312.pyc and b/backend/app/__pycache__/main.cpython-312.pyc differ
diff --git a/backend/app/__pycache__/models.cpython-312.pyc b/backend/app/__pycache__/models.cpython-312.pyc
index 2d459cc..b108f1a 100644
Binary files a/backend/app/__pycache__/models.cpython-312.pyc and b/backend/app/__pycache__/models.cpython-312.pyc differ
diff --git a/backend/app/main.py b/backend/app/main.py
index 2d3863c..83e0430 100644
--- a/backend/app/main.py
+++ b/backend/app/main.py
@@ -88,17 +88,17 @@ def _migrate_add_missing_columns(sync_conn):
         if isinstance(col_type, sa.Text):
             sql_type = "TEXT"
         elif isinstance(col_type, sa.String):
-            sql_type = "VARCHAR(500)"
+            sql_type = f"VARCHAR({col_type.length})"
         else:
             sql_type = "TEXT"
 
         if dialect == "sqlite":
             sync_conn.execute(
-                sa.text(f'ALTER TABLE {table_name} ADD COLUMN "{col_name}" TEXT NOT NULL DEFAULT "{default}"')
+                sa.text(f"ALTER TABLE {table_name} ADD COLUMN \"{col_name}\" TEXT NOT NULL DEFAULT '{default}'")
             )
         else:
             sync_conn.execute(
-                sa.text(f'ALTER TABLE {table_name} ADD COLUMN "{col_name}" {sql_type} NOT NULL DEFAULT "{default}"')
+                sa.text(f"ALTER TABLE {table_name} ADD COLUMN \"{col_name}\" {sql_type} NOT NULL DEFAULT '{default}'")
             )
 
         print(f"  ✓ Added {table_name}.{col_name}")