Re: [HACKERS] Predicate Locks for writes?

On Wed, Oct 11, 2017 at 11:51 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
> I'm inclined to believe Robert's hypothesis that there is some race
> condition there.
>
> The question is whether that still constitutes a serializability
> problem since we haven't done anything with the data, just passed it
> upwards to be modified.

Well, the question is whether passing it upwards constitutes reading
it.  I kind of suspect it does.  The plan tree isn't just blindly
propagating values upward but stuff with them.  There could be quite a
bit between the ModifyTable node and the underlying scan if DELETE ..
FROM or UPDATE .. USING is in use.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company


-- 
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers