On Wed, Jan 20, 2016 at 3:55 AM, Gasper Zejn <zelo.z...@gmail.com> wrote:
> I was wondering if PostgreSQL adds new tuple if data is not changed > when using UPDATE. It turns out it does add them and I think it might > be beneficial not to add a new tuple in this case, since it causes a > great deal of maintenance: updating indexes, vacuuming table and > index, also heap fragmentation. If you have one or more tables on which you routinely updated rows to the values they already have, you might want to attach an update trigger using the suppress_redundant_updates_trigger() function. http://www.postgresql.org/docs/current/interactive/functions-trigger.html A better solution, where possible, is to use the WHERE clause to avoid the update attempt where the new values are not distinct from the old ones. -- Kevin Grittner EDB: 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
