Re: Update / Lock (and ShareLock) question - Mailing list pgsql-general

From Tom Lane
Subject Re: Update / Lock (and ShareLock) question
Date
Msg-id 3165.1215785632@sss.pgh.pa.us
Whole thread Raw
In response to Update / Lock (and ShareLock) question  (Augustin Amann <augustin@waw.com>)
Responses Re: Update / Lock (and ShareLock) question
List pgsql-general
Augustin Amann <augustin@waw.com> writes:
> During lock, we could see things like this in log file:
> Process 5556 waits for ShareLock on transaction 14910066; blocked by
> process 4940.

What that really means is that the first process is waiting for a row
lock that's held by the second one --- that is, it's trying to update a
row that the second transaction has updated and not yet committed.

> Why waiting update are not simply queued ?

Uh, that's exactly what's happening.

            regards, tom lane

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