Re: Questions about update, delete, ctid...

[Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>]

DANTE Alexandra <Alexandra(dot)Dante(at)bull(dot)net> writes:
>     - during a SELECT query on a tuple just updated and commited, does 
> the executor first detect the old tuple and then via the c_tid link go 
> to the new version of the tuple ? or go directly to the new version ?

Neither.  SELECT doesn't care about update relationships, it just
returns whatever row version is current according to its snapshot.
It's only UPDATE/DELETE that are constrained to act on the most
current version of each row.

			regards, tom lane