On Wednesday, June 20, 2012 01:10:03 PM Sam Z J wrote: > Hi all > > I'm curious how is wildcards at both ends implemented, e.g. LIKE '%str%' > How efficient is it if that's the only search criteria against a large > table? how much does indexing the column help and roughly how much more > space is needed for the index? >
Indexing helps not at all. If the search string starts with a wildcard you will always get a sequential scan of the whole table. Look at the full text search documentation for a better approach. -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
