Horton

Re: delta relations in AFTER triggers

Craig Ringer <craig@2ndquadrant.com>

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From: Craig Ringer <craig@2ndquadrant.com>
To: Kevin Grittner <kgrittn@ymail.com>, Heikki Linnakangas <hlinnakangas@vmware.com>, Amit Khandekar <amit.khandekar@enterprisedb.com>
Cc: Robert Haas <robertmhaas@gmail.com>, David Fetter <david@fetter.org>, Alvaro Herrera <alvherre@2ndquadrant.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2014-09-25T01:58:32Z
Lists: pgsql-hackers 
On 08/28/2014 05:03 AM, Kevin Grittner wrote:
> I don't have to squint that hard -- I've always been comfortable
> with the definition of a table as a relation variable, and it's not
> too big a stretch to expand that to a tuplestore.  ;-)  In fact, I
> will be surprised if someone doesn't latch onto this to create a
> new "declared temporary table" that only exists within the scope of
> a compound statement (i.e., a BEGIN/END block).  You would DECLARE
> them just like you would a scalar variable in a PL, and they would
> have the same scope.
> 
> I'll take a look at doing this in the next couple days, and see
> whether doing it that way is as easy as it seems on the face of it.

Oracle's TABLE variables in PL/SQL are quite similar; it might be worth
observing how they work for comparison.

-- 
 Craig Ringer                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services

Commits

  1. Don't permit transition tables with TRUNCATE triggers.

  2. Pass EXEC_FLAG_REWIND when initializing a tuplestore scan.

  3. Faster expression evaluation and targetlist projection.

  4. Remove obsoleted code relating to targetlist SRF evaluation.

  5. Implement syntax for transition tables in AFTER triggers.