SQL Server - Do automatically created column statistics get dropped automatically after time?

Question

The retired SQL Server 2000 documentation https://www.microsoft.com/en-us/download/details.aspx?id=51958 states:

"The statistics generated for a column can be deleted if you no longer want to retain and maintain them. Statistics created on columns by SQL Server (when the AUTO_CREATE_STATISTICS database option is set to ON) are aged and dropped automatically."

Obviously this is old documentation related to SQL Server 2000, but I can't find anything official that is more current and says otherwise or that the behaviour is different now. Can anyone answer definitively? Thanks..

Answer 1

SQL Server, under no version or circumstance, will automatically remove statistics objects, unless the underlying object (table/view/index) is removed.

Use DROP STATISTICS ... T-SQL or use the SSMS GUI to drop unnecessary statistics, but only do that if you are certain they are not needed.