fix(records): remove sync_id from mark_previous_generation_as_deleted index (#5144)

sync_id isn't a filter anymore in the `deleteOutdatedRecords` query.
c2e9ba4
his commit replaces the existing index by a new one without the sync_id
field

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Author: TBonnin

packages/records/lib/db/migrations/20251211175100_records_outdated_records_indexes.ts

@@ -0,0 +1,26 @@
+import type { Knex } from 'knex';
+
+export const config = {
+    transaction: false
+};
+
+export async function up(knex: Knex): Promise<void> {
+    // adding a more specific index used by the "mark previous generation as deleted" query
+    // removing sync_id from the index as it's not used in the query filter anymore
+    // pg prevents adding index to parent table concurrently - must be done on each partition
+    for (let p = 0; p < 256; p++) {
+        await knex.raw(
+            `CREATE INDEX CONCURRENTLY IF NOT EXISTS records_p${p}_mark_previous_generation_as_deleted_v2
+                ON nango_records.records_p${p}(connection_id, model, sync_job_id)
+                INCLUDE (id)
+                WHERE deleted_at IS NULL;`
+        );
+    }
+
+    // droping existing indexes that are not being used by pg
+    for (let p = 0; p < 256; p++) {
+        await knex.raw(`DROP INDEX CONCURRENTLY IF EXISTS records_p${p}_mark_previous_generation_as_deleted;`);
+    }
+}
+
+export async function down(): Promise<void> {}