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Old 11-09-06, 03:09
vk101 vk101 is offline
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Deferred checking

Apparently MySQL does not support deferred checking. I know in basic terms what deferred checking is, but I'm not sure what implications having it (or not having it) in your DBMS is.

Could somebody please explain why the MySQL documentation explains that without deferred checking, having a foreign key reference its own row is not possible? I'm not sure why that is... (And did it mean when the foreign key references its own row, or when it references any other row in the same table?)

Also, apparently for ON DELETE/UPDATE, NO ACTION and RESTRICT are the same because there's no deferred checking. The docs say it's because ON DELETE/UPDATE NO ACTION is with deferred checking, but I just can't wrap my head around understanding why this is...

Any help on this would be great, thanks a lot.
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Old 11-09-06, 08:28
r937 r937 is offline
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