MySQL Bugs: #119413: Intersection order

Bug #119413	Intersection order
Submitted:	17 Nov 2025 23:52	Modified:	7 Dec 2025 21:06
Reporter:	wenwen wen	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Server: Optimizer	Severity:	S3 (Non-critical)
Version:	mysql Ver 9.4.	OS:	Any
Assigned to:		CPU Architecture:	Any

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Description:
SELECT NULL INTERSECT SELECT 1 returns empty but SELECT 1 INTERSECT SELECT NULL gives the result 1. The order of the intersection changes then the results are different.

How to repeat:
You could change the order of INTERSECT but must have NULL at one side.

Verified as described.