fix(reflection bug): Fixed bug causing TypeError when using metadata.…

…reflect()

duckdb_engine/__init__.py

@@ -17,14 +17,15 @@
 
 import duckdb
 import sqlalchemy
-from sqlalchemy import pool, text, util
+from sqlalchemy import pool, text, util, select, sql
 from sqlalchemy import types as sqltypes
 from sqlalchemy.dialects.postgresql import UUID
 from sqlalchemy.dialects.postgresql.base import (
     PGDialect,
     PGIdentifierPreparer,
     PGInspector,
     PGTypeCompiler,
+    pg_catalog,
 )
 from sqlalchemy.dialects.postgresql.psycopg2 import PGDialect_psycopg2
 from sqlalchemy.engine.default import DefaultDialect
@@ -34,6 +35,7 @@
 from sqlalchemy.exc import NoSuchTableError
 from sqlalchemy.ext.compiler import compiles
 from sqlalchemy.sql.selectable import Select
+from sqlalchemy.sql import bindparam
 
 from ._supports import has_comment_support
 from .config import apply_config, get_core_config
@@ -601,6 +603,31 @@ def get_multi_columns(
 
         return columns.items()
 
+    def _comment_query(self, schema, has_filter_names, scope, kind):
+        relkinds = self._kind_to_relkinds(kind)
+        query = (
+            select(
+                pg_catalog.pg_class.c.relname,
+                pg_catalog.pg_description.c.description,
+            )
+            .select_from(pg_catalog.pg_class)
+            .outerjoin(
+                pg_catalog.pg_description,
+                sql.and_(
+                    pg_catalog.pg_class.c.oid
+                    == pg_catalog.pg_description.c.objoid,
+                    pg_catalog.pg_description.c.objsubid == 0,
+                ),
+            )
+            .where(self._pg_class_relkind_condition(relkinds))
+        )
+        query = self._pg_class_filter_scope_schema(query, schema, scope)
+        if has_filter_names:
+            query = query.where(
+                pg_catalog.pg_class.c.relname.in_(bindparam("filter_names"))
+            )
+        return query
+
 
 if sqlalchemy.__version__ >= "2.0.14":
     from sqlalchemy import TryCast  # type: ignore[attr-defined]

duckdb_engine/tests/test_reflection.py

@@ -0,0 +1,12 @@
+from sqlalchemy import MetaData, create_engine, text
+
+engine = create_engine("duckdb:///:memory:")
+metadata = MetaData()
+with engine.connect() as conn:
+    conn.execute(text("CREATE TABLE tbl(col1 INTEGER)"))
+    conn.commit()
+try:
+    metadata.reflect(engine)
+except Exception as e:
+    print("Exception: " + str(e))
+    raise AssertionError