Horton

ALTER TABLE ADD COLUMN fast default

Andrew Dunstan <andrew.dunstan@2ndquadrant.com>

View thread View on postgr.es
From: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
To: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2017-12-06T14:36:23Z
Lists: pgsql-hackers

Attachments

Attached is a patch for $subject. It's based on Serge Reilau's patch of
about a year ago, taking into account comments made at the time. with
bitrot removed and other enhancements such as documentation.

Essentially it stores a value in pg_attribute that is used when the
stored tuple is missing the attribute. This works unless the default
expression is volatile, in which case a table rewrite is forced as
happens now.

Comments welcome.


cheers


andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services

Commits

  1. Clean up treatment of missing default and CHECK-constraint records.

  2. Fast ALTER TABLE ADD COLUMN with a non-NULL default

  3. Fix application of identity values in some cases