Recreate foreign key constraints for game cover and header images in DB #730 (fixes #724 #725 #726)

app/src/main/resources/db/migration/V2.1.1__Recreate_game_image_fks_without_unique_indexes.sql

@@ -0,0 +1,70 @@
+-- Flyway Migration: V2.1.1
+-- Purpose: Fully eliminate unintended uniqueness on GAME.COVER_IMAGE_ID / HEADER_IMAGE_ID
+--          by dropping and recreating foreign keys and removing lingering unique indexes
+-- Context:
+--   * Original schema created UNIQUE constraints (UK52... cover, UK30... header).
+--   * V2.1.0.1 dropped those constraints but H2 left behind unique indexes (UK52..._INDEX_n etc.).
+-- Strategy:
+--   1. Drop the foreign keys (idempotent).
+--   2. Drop any remaining unique constraints (defensive repeat) and their indexes.
+--   3. Recreate NON-UNIQUE supporting indexes explicitly (optional but good for lookups).
+--   4. Recreate the foreign keys cleanly without reintroducing uniqueness.
+--   5. All steps are idempotent / tolerant so reruns don't fail.
+
+/******************************************************************************************
+ * 1. Drop foreign keys so their backing indexes can be dropped safely
+ ******************************************************************************************/
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS FK_GAME_COVER_IMAGE;
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS FK_GAME_HEADER_IMAGE;
+
+-- Also attempt legacy hashed names (in case rename earlier never ran)
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS FK6CVB43REAYSNYPI0XDY6HQTVF; -- old cover FK
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS FK8N86NDPGKMOO7YOLX6HL8N84G;
+-- old header FK
+
+/******************************************************************************************
+ * 2. Drop any lingering UNIQUE constraints again (defensive) and their indexes
+ ******************************************************************************************/
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS UK52RQ62FLPBNTI77BYKM7UAHKQ; -- old unique cover
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS UK30B16LLQV54H40XIOGP7T9P35; -- old unique header
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS UQ_GAME_COVER_IMAGE_ID; -- friendly (future) name
+ALTER TABLE GAME
+    DROP CONSTRAINT IF EXISTS UQ_GAME_HEADER_IMAGE_ID;
+-- friendly (future) name
+
+-- Drop possible leftover unique indexes (multiple variants tried)
+DROP INDEX IF EXISTS UK52RQ62FLPBNTI77BYKM7UAHKQ_INDEX_2;
+DROP INDEX IF EXISTS UK52RQ62FLPBNTI77BYKM7UAHKQ_INDEX_1;
+DROP INDEX IF EXISTS UK30B16LLQV54H40XIOGP7T9P35_INDEX_2;
+DROP INDEX IF EXISTS UK30B16LLQV54H40XIOGP7T9P35_INDEX_1;
+
+/******************************************************************************************
+ * 3. Create explicit NON-UNIQUE indexes (only if missing)
+ ******************************************************************************************/
+CREATE INDEX IF NOT EXISTS IDX_GAME_COVER_IMAGE ON GAME (COVER_IMAGE_ID);
+CREATE INDEX IF NOT EXISTS IDX_GAME_HEADER_IMAGE ON GAME (HEADER_IMAGE_ID);
+
+/******************************************************************************************
+ * 4. Recreate foreign keys (non-unique by definition)
+ ******************************************************************************************/
+ALTER TABLE GAME
+    ADD CONSTRAINT FK_GAME_COVER_IMAGE FOREIGN KEY (COVER_IMAGE_ID) REFERENCES IMAGE (ID);
+ALTER TABLE GAME
+    ADD CONSTRAINT FK_GAME_HEADER_IMAGE FOREIGN KEY (HEADER_IMAGE_ID) REFERENCES IMAGE (ID);
+
+/******************************************************************************************
+ * 5. (Optional manual verification after migration)
+ * -- SELECT INDEX_NAME, NON_UNIQUE, COLUMN_NAME FROM INFORMATION_SCHEMA.INDEXES
+ * --  WHERE TABLE_NAME='GAME' AND COLUMN_NAME IN ('COVER_IMAGE_ID','HEADER_IMAGE_ID');
+ * Expected: ONLY non-unique indexes (NON_UNIQUE=TRUE) for those columns.
+ ******************************************************************************************/
+
+-- End of migration.
+