Re: LIKE operator and indexes

On Fri, 31 May 2002, Marc Mitchell wrote:

> Can anyone provide definitive information and/or points of reference within
> the documentation about the ability of the query optimizer to use indexes
> when processing a "LIKE" operator on a String column?
>
> My assumption is that
>
> "SELECT * FROM customer WHERE name LIKE 'GENERAL%';"
>
> should benefit from the existence of a BTREE index on the "customer.name"
> column.  I know this is the case is most other RDBMS's I've used including
> Postgres's ancestor Ingres.

If you are in "C" locale, and have an anchored like or regex, indexes
should be considered.  If you're in a different locale, the optimization
is turned off.