Re: Concurrency Question - Mailing list pgsql-general

From Gregory Stark
Subject Re: Concurrency Question
Date
Msg-id 87abtvei9g.fsf@oxford.xeocode.com
Whole thread Raw
In response to Concurrency Question  (Perry Smith <pedz@easesoftware.com>)
List pgsql-general
"Perry Smith" <pedz@easesoftware.com> writes:

> Looking at the documentation above, I would expect the insert into A to get a
> Row exclusive lock for table A.  And, I'm guessing it would  get an ACCESS
> SHARE lock for table B.  But this would not prevent the  delete from B from
> happening at the same time (if I am reading this  correctly).

The bit you quoted was for tables. The RI trigger does indeed take a share
lock on the referenced record in table B which prevents it from being deleted.
(In older versions it used to take an exclusive lock because there were no
share locks on records.)

--
  Gregory Stark
  EnterpriseDB          http://www.enterprisedb.com


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