Re: LIKE search and performance - Mailing list pgsql-performance

From Guido Neitzer
Subject Re: LIKE search and performance
Date
Msg-id 532C0F0C-117B-45A1-9CA2-66CA9ECA711F@event-s.net
Whole thread Raw
In response to LIKE search and performance  ("Andy" <frum@ar-sd.net>)
List pgsql-performance
Am 23.05.2007 um 09:08 schrieb Andy:

> I have a table with varchar and text columns, and I have to search
> through these text in the whole table.
>
> An example would be:
> SELECT * FROM table
>                              WHERE name like '%john%' or street
> like '%srt%'
>
> Anyway, the query planner always does seq scan on the whole table
> and that takes some time. How can this be optimized or made in
> another way to be faster?

The problem is that normal indexes cannot be used for "contains"
queries.

If you need fulltext search capabilities you have to take a look at
tsearch2 or an external search engine like Lucene.

cug

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