Re: UPSERT wiki page, and SQL MERGE syntax

Peter Geoghegan <pg@heroku.com> wrote:

> There is no danger of UPDATE before row-level triggers firing
> without then updating (unless the xact aborts, but you know what
> I mean).

Well, let's make sure I do know what you mean.  If a BEFORE UPDATE
... FOR EACH ROW trigger returns NULL, the UPDATE will be skipped
without error, right?  The BEFORE UPDATE triggers will run before
the UPDATE if a duplicate is found, and the return value will be
treated in the usual manner, replacing values and potentially
skipping the update?

--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company