mock store tables stubbed in db schema

database_migrations/000013_sync_group_table_state.up.sql

@@ -8,9 +8,9 @@ CREATE TABLE sync_groups (
 CREATE TABLE sync_group_listings (
 	sync_group_id	INTEGER		NOT NULL 	REFERENCES sync_groups,
 	order_index		INTEGER		NOT NULL,
-	platform		platform,
-	shop_id			TEXT,
-	listing_id		TEXT,
+	platform		platform	NOT NULL,
+	shop_id			TEXT		NOT NULL,
+	listing_id		TEXT		NOT NULL,
 
 	PRIMARY KEY (sync_group_id, order_index)
 );