Re: this is in plain text (row level locks)

Bruce Momjian <pgman@candle.pha.pa.us> writes:
> Sailesh Krishnamurthy wrote:
>> Does pgsql only record X locks on the individual tuples on-disk or
>> does it do so for S locks as well ? 

> We don't need to shared lock individual rows because of MVCC --- well,
> we sort of do by recording our xid in our proc structure, so folks don't
> change things underneath us.  We prevent expired rows from disappearing
> from the disk by others looking at our proc start xid.

This is actually an issue though.  Row-level shared locks would be
really nice to have for foreign-key handling.  Right now we have to
use X locks for those, and that leads to deadlocking problems for
applications.
        regards, tom lane