1 files changed, 74 insertions, 0 deletions
diff --git a/db/post_migrate/20230404031041_swap_epic_user_mentions_note_id_to_bigint_for_gitlab_dot_com.rb b/db/post_migrate/20230404031041_swap_epic_user_mentions_note_id_to_bigint_for_gitlab_dot_com.rb
new file mode 100644
index 00000000000..3d0478c15dd
--- /dev/null
+++ b/db/post_migrate/20230404031041_swap_epic_user_mentions_note_id_to_bigint_for_gitlab_dot_com.rb
@@ -0,0 +1,74 @@
+# frozen_string_literal: true
+
+class SwapEpicUserMentionsNoteIdToBigintForGitlabDotCom < Gitlab::Database::Migration[2.1]
+  include Gitlab::Database::MigrationHelpers::ConvertToBigint
+
+  disable_ddl_transaction!
+
+  TABLE_NAME = 'epic_user_mentions'
+
+  def up
+    return unless should_run?
+
+    swap
+  end
+
+  def down
+    return unless should_run?
+
+    swap
+  end
+
+  def swap
+    # This will replace the existing epic_user_mentions_on_epic_id_and_note_id_index
+    add_concurrent_index TABLE_NAME, [:epic_id, :note_id_convert_to_bigint], unique: true,
+      name: 'epic_user_mentions_on_epic_id_and_note_id_convert_to_bigint'
+
+    # This will replace the existing epic_user_mentions_on_epic_id_index
+    add_concurrent_index TABLE_NAME, :epic_id, unique: true,
+      name: 'tmp_epic_user_mentions_on_epic_id_index',
+      where: 'note_id_convert_to_bigint IS NULL'
+
+    # This will replace the existing index_epic_user_mentions_on_note_id
+    add_concurrent_index TABLE_NAME, :note_id_convert_to_bigint, unique: true,
+      name: 'index_epic_user_mentions_on_note_id_convert_to_bigint',
+      where: 'note_id_convert_to_bigint IS NOT NULL'
+
+    # This will replace the existing fk_rails_1c65976a49
+    add_concurrent_foreign_key TABLE_NAME, :notes, column: :note_id_convert_to_bigint,
+      name: 'fk_epic_user_mentions_note_id_convert_to_bigint',
+      on_delete: :cascade
+
+    with_lock_retries(raise_on_exhaustion: true) do
+      execute "LOCK TABLE notes, #{TABLE_NAME} IN ACCESS EXCLUSIVE MODE"
+
+      execute "ALTER TABLE #{TABLE_NAME} RENAME COLUMN note_id TO note_id_tmp"
+      execute "ALTER TABLE #{TABLE_NAME} RENAME COLUMN note_id_convert_to_bigint TO note_id"
+      execute "ALTER TABLE #{TABLE_NAME} RENAME COLUMN note_id_tmp TO note_id_convert_to_bigint"
+
+      function_name = Gitlab::Database::UnidirectionalCopyTrigger
+        .on_table(TABLE_NAME, connection: connection)
+        .name(:note_id, :note_id_convert_to_bigint)
+      execute "ALTER FUNCTION #{quote_table_name(function_name)} RESET ALL"
+
+      execute 'DROP INDEX IF EXISTS epic_user_mentions_on_epic_id_and_note_id_index'
+      rename_index TABLE_NAME, 'epic_user_mentions_on_epic_id_and_note_id_convert_to_bigint',
+        'epic_user_mentions_on_epic_id_and_note_id_index'
+
+      execute 'DROP INDEX IF EXISTS epic_user_mentions_on_epic_id_index'
+      rename_index TABLE_NAME, 'tmp_epic_user_mentions_on_epic_id_index',
+        'epic_user_mentions_on_epic_id_index'
+
+      execute 'DROP INDEX IF EXISTS index_epic_user_mentions_on_note_id'
+      rename_index TABLE_NAME, 'index_epic_user_mentions_on_note_id_convert_to_bigint',
+        'index_epic_user_mentions_on_note_id'
+
+      execute "ALTER TABLE #{TABLE_NAME} DROP CONSTRAINT IF EXISTS fk_rails_1c65976a49"
+      rename_constraint(TABLE_NAME, 'fk_epic_user_mentions_note_id_convert_to_bigint', 'fk_rails_1c65976a49')
+    end
+  end
+
+  def should_run?
+    com_or_dev_or_test_but_not_jh?
+  end
+end