How big should a SQL transaction log be?

Question

Although there is no one optimal value for Transaction Log File initial size and auto-growth that fits all situations, but setting the initial size of the SQL Server Transaction Log file to 20-30% of the database data file size and the auto-growth to a large amount, above 1024MB, based on your database growth plan can . 22 апр. 2019 г.

What is a good log file size?

No more than 2 or 3 entries per user action though, unless you are doing batch operations. Don't put more than 2MB in a file, so the user can email it you. Don't keep more than 50MB of logs, because it's probably not your space you are wasting here.

How big can a SQL transaction be?

About the size, there is no specific size limit in SQL Server, they can theoretically modify any amount of data without problems. The practical limit is really the size of the transaction log file of the target database.

Why is my SQL transaction log so big?

Large database transactions, such as importing large amounts of data, can lead to a large transaction log file. Transaction log backups not happening fast enough causes the SQL log file to become huge. SQL log files also enlarge due to incomplete replication or availability group synchronization.

Does transaction log size affect performance?

If the transaction log file is full in the SQL Server database, it degrades the performance of the SQL Server. It also slows down the speed of the transactional log backup process. In addition, the over-sized transaction logs decrease the disk space also because old transaction logs are not removed yet.

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