Re: Strange situation with two tables. - Mailing list pgsql-novice

From Oliver Elphick
Subject Re: Strange situation with two tables.
Date
Msg-id 1031756947.2061.444.camel@linda
Whole thread Raw
In response to Re: Strange situation with two tables.  (Terry Yapt <yapt@technovell.com>)
List pgsql-novice
On Wed, 2002-09-11 at 15:41, Terry Yapt wrote:
> If I understand you and
>
> USER1 starts this pl/pgsql body function
>     BEGIN
>        SELECT count(*) AS c1 FROM debits;
>        ........
>        ........  -- Here USER2 INSERTS a new row in debits table. --
>        ........
>        SELECT count(*) AS c2 FROM debits
>        IF c1 = c2 THEN
>           RETURN true
>        ELSE
>           RETURN false
>        END IF;
>     END;
>
> This functions returns TRUE ?  It is right ?

If USER2's transaction has been committed, if the isolation level is
'read committed' the function will return false but if the isolation
level is 'serializable' it will return true.

If USER2's transaction is uncommitted, the function will return true
whatever the isolation level.


--
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight, UK
http://www.lfix.co.uk/oliver
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                 ========================================
     "I am crucified with Christ; nevertheless I live; yet
      not I, but Christ liveth in me; and the life which I
      now live in the flesh I live by the faith of the Son
      of God, who loved me, and gave himself for me."
                                         Galatians 2:20


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