Re: Index not always being used
Holger Jakobs <[email protected]>
| Newsgroups | gmane.comp.db.postgresql.admin |
|---|---|
| Message-ID | <[email protected]> |
Hi, A good solution would be to add another B-Tree index. The planner would choose this one in case of a search using "=" and the trigram index when using "like", "similar to" or "~" (regexp). A trigram index is not suitable for a "=" comparison. Regards, Holger Am 29.08.19 um 16:15 schrieb John Scalia: > I’ve got a table with approximately 5.5 million rows, and one column that is frequently searched is of type varchar(50) and we just put a trigram index on it. Now, if we search “where bld_city = ‘baskingridge’”, explain says a sequential table scan is going to be used, but if I change the query to use “where bold_city like ‘basking%’”, then explain correctly shows that a bitmap index scan will be performed. Why would these two forms use different approaches? I’m a bit confused. > — > Jay > > Sent from my iPad > -- Holger Jakobs, Bergisch Gladbach instant messaging: xmpp:[email protected] +49 178 9759012 <tel:+491789759012> oder +49 2202 817157 <tel:+492202817157>