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During "Online" DDL, Some DML Waits On Semaphore Last Locked In " line 53" (Doc ID 2480928.1)

Last updated on APRIL 06, 2020

Applies to:

MySQL Server - Version 5.7 and later
Information in this document applies to any platform.



An otherwise non-locking ALTER TABLE .. ADD KEY leads to an expected long semaphore wait near the end.
InnoDB status show it like this: (note: line 53 )


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