fix diff round-trip comparison

pkg/readers/pgsql/queries.go

@@ -538,8 +538,13 @@ func (r *Reader) queryCheckConstraints(schemaName string) (map[string][]*models.
 		FROM information_schema.table_constraints tc
 		JOIN information_schema.check_constraints cc
 			ON tc.constraint_name = cc.constraint_name
+			AND cc.constraint_schema = tc.table_schema
+		JOIN pg_catalog.pg_constraint pc
+			ON pc.conname = tc.constraint_name
+			AND pc.connamespace = (SELECT oid FROM pg_namespace WHERE nspname = tc.table_schema)
 		WHERE tc.constraint_type = 'CHECK'
 		  AND tc.table_schema = $1
+		AND pc.contype = 'c'
 	`
 
 	rows, err := r.conn.Query(r.ctx, query, schemaName)
@@ -579,7 +584,12 @@ func (r *Reader) queryIndexes(schemaName string) (map[string][]*models.Index, er
 			indexname,
 			indexdef
 		FROM pg_indexes
+		JOIN pg_catalog.pg_class idx ON idx.relname = indexname
+		JOIN pg_catalog.pg_index i ON i.indexrelid = idx.oid
+		JOIN pg_catalog.pg_namespace idx_ns ON idx_ns.oid = idx.relnamespace
 		WHERE schemaname = $1
+		  AND idx_ns.nspname = schemaname
+		  AND NOT i.indisprimary
 		ORDER BY schemaname, tablename, indexname
 	`