Re: table-level and row-level locks. - Mailing list pgsql-hackers

From Jenny -
Subject Re: table-level and row-level locks.
Date
Msg-id BAY1-F74sc2zTqgiRwM0002dbfa@hotmail.com
Whole thread Raw
In response to table-level and row-level locks.  ("Jenny -" <nat_lazy@hotmail.com>)
List pgsql-hackers
>A row lock is represented by storing the locking transaction's ID in
>xmax and setting the HEAP_MARKED_FOR_UPDATE infomask bit.

Where is 'xmax' found? is it at code level or on disk?
thanks
Jenny


>From: Tom Lane <tgl@sss.pgh.pa.us>
>To: suzukikui@nttdata.co.jp
>CC: pgsql-hackers@postgresql.org
>Subject: Re: [HACKERS] table-level and row-level locks. Date: Wed, 20 Aug 
>2003 14:45:23 -0400
>
>Koichi Suzuki <suzukikui@nttdata.co.jp> writes:
> > I need to know where such "lock marks" are stored in the source level.
>
>A row lock is represented by storing the locking transaction's ID in
>xmax and setting the HEAP_MARKED_FOR_UPDATE infomask bit.  The bit is
>needed to distinguish this from the case where the transaction is
>deleting the tuple.
>
>            regards, tom lane
>
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