Re: Rules and Triggers

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От Michael Paesold
Тема Re: Rules and Triggers
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Msg-id 002101c25964$e5e4e460$4201a8c0@beeblebrox
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Ответ на Re: Rules and Triggers  ("Adam Erickson" <adamre@cox.net>)
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Ross J. Reedstrom wrote:

> An important thing to remember about rules vs. triggers: Rules operate
> on an SQL _query_ that involves the table (or view) that the rule is
> attached to, whereas triggers operate on the individual _tuples_ of the
> table they are attached to. Rules act to rewrite the incoming query,
> at the very earliest step: just after parsing, but before planning and
> optimizing. So rules _always_ act first. Triggers act when storage gets
> hit: when the optimizer has choosen a plan, and passes it to the executor
> for, well, execution.
> 
> Ross

Thanks alot, again I understand a little bit more.

You're great, guys!

Regards, Michael Paesold



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