SQL Interview: 110 Long restores and restarts

SQL Interview: 110 Long restores and restarts

This is a post in the SQL Interview series. These aren’t trick or gotcha questions, they’re just questions designed to scope out a candidate’s knowledge around SQL Server and Azure SQL Database.

Section: Administration Level: Intro

Question:

You are restoring a database backup. The restore finished reading pages 10 minutes ago, but the database still shows that it is restoring.

Can you speed up the restoring phase by restarting the server? If so, should you do that? If not, why not?

Answer:

When SQL Server reports that a restore is still in progress after all pages are read, it’s usually in the transaction recovery phase, which happens after data and log pages are loaded.

That phase includes:

  • Redo (roll forward) — applying committed transactions from the backup’s log.
  • Undo (roll back) — undoing any incomplete or uncommitted transactions.

This ensures the restored database is transactionally consistent before it’s brought online. Depending on database size, log activity, or I/O performance, this can take minutes or even hours.

Restarting the SQL Server instance will not speed it up. In fact, it will make things slower or worse.

If you restart the service during restore, the operation will abort. When you restart and attempt again, SQL Server will have to start the entire restore process over — re-reading and reapplying everything from scratch.

You gain nothing; in fact you lose time, so no, you should not restart. Let it finish.

The fact that it’s showing Restoring after reading pages means it’s still completing recovery internally — SQL Server hasn’t hung; it’s just working through redo/undo.

2026-01-14