Fun With Undocumented Trace Flags

Joe Obbish has a list of 45 undocumented trace flags:

Below is a list of trace flags which, as far as I can tell, have never been publicly documented. I did not fully investigate many of them and many of the descriptions are just guesses. I make no guarantees and none of these should be used in production. All tests were performed on SQL Server 2017 CU2 with trace flags enabled at the global level.

This is combining a bit of database archaeology and database anthropology.

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