Assume that you enable Trace Flag (TF) 460 in SQL Server 2017. When you use an INSERT INTO table variable in the ELSE block of the IF...ELSE... condition statement, it throws a truncation error in the IF block itself.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
This issue is fixed in the following cumulative update for SQL Server:
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Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
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