Query Store and Log Backups

A question that came up recently around Query Store is what happens when there are log backups in use on the database. Let's talk about it. Query Store and Log Backups The core of the answer is very simple. Query Store, like any other data written to a database, whether a system table or a user table, is a logged operation. So, when you backup the database, you're backing up Query Store data. When you backup the logs, you're also backing up Query Store data. A point in time will include all the data written to the Query Store at that point. However, that's the kicker. At what point was the Query Store information written to disk? By default, there's a fifteen minute cycle before the Query Store moves the…
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DBA 101: Why is my log file full?

SQL Server
This question comes up constantly in different venues. I see it sometimes 2-3 times a day on SQL Server Central. I know it pops up at least once a week on Ask SSC. I’m sure I’ve seen it on Twitter #sqlhelp. “Why is my log file growing?” and “Why is my log file full” are heard regularly. Or, the variation, “I ran a full backup but the log file is still full/growing.” occasionally comes up. The people asking these questions are frequently, even appropriately, frantic. I’m writing this blog post for two reasons. First, to try to add a little bit of weight to what must surely be one of the most searched for phrases on the internet when it comes to SQL Server. Second, just to have a shorthand…
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