On 12/30/2016 12:33 AM, David G. Johnston wrote:
On Thu, Dec 29, 2016 at 4:21 PM, Job <Job@xxxxxxxxxxxxxxxxxxxx
<mailto:Job@colliniconsulting.it >>wrote:
Hello,
in Postgresql 9.6 we have a query running on a very large table
based, in some cases, on a like statement:
... WHERE FIELD='CODE' OR FIELD LIKE 'CODE_%'
Which type of index can i create to speed to the search when the
"like" case happens?
GIST
https://www.postgresql.org/docs/9.6/static/pgtrgm.html
https://www.postgresql.org/docs/9.6/static/btree-gist.html
For prefix queries, it's also possible to use simple btree index with varchar_pattern_ops.
https://www.postgresql.org/docs/9.6/static/indexes-opclass. html
Even knowing that this feature exists I don't know that I could have found it within a reasonable amount of time in its present location. A few cross-references from elsewhere (probably at least the functions part of the documentation) would make learning about the capability a lot easier.
David J.
