Add indexes to support messages foreign key constraints

ts/test-node/sql/migration_1120_test.ts

@@ -0,0 +1,53 @@
+// Copyright 2024 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { assert } from 'chai';
+import type { Database } from '@signalapp/better-sqlite3';
+import SQL from '@signalapp/better-sqlite3';
+import { updateToVersion } from './helpers';
+
+describe('SQL/updateToSchemaVersion1120', () => {
+  let db: Database;
+  beforeEach(() => {
+    db = new SQL(':memory:');
+    updateToVersion(db, 1120);
+  });
+
+  afterEach(() => {
+    db.close();
+  });
+
+  it('uses index for deleting edited messages', () => {
+    const details = db
+      .prepare(
+        `EXPLAIN QUERY PLAN 
+            DELETE FROM edited_messages WHERE messageId = 'messageId';
+        `
+      )
+      .all()
+      .map(step => step.detail)
+      .join(', ');
+
+    assert.strictEqual(
+      details,
+      'SEARCH edited_messages USING COVERING INDEX edited_messages_messageId (messageId=?)'
+    );
+  });
+
+  it('uses index for deleting mentions', () => {
+    const details = db
+      .prepare(
+        `EXPLAIN QUERY PLAN 
+            DELETE FROM mentions WHERE messageId = 'messageId';
+          `
+      )
+      .all()
+      .map(step => step.detail)
+      .join(', ');
+
+    assert.strictEqual(
+      details,
+      'SEARCH mentions USING COVERING INDEX mentions_messageId (messageId=?)'
+    );
+  });
+});