Re: ILIKE vs indices

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: James Cloos <cloos(at)jhcloos(dot)com>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: ILIKE vs indices
Date: 2012-12-28 23:41:29
Message-ID: 22960.1356738089@sss.pgh.pa.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

James Cloos <cloos(at)jhcloos(dot)com> writes:
> Is there any contraindication to recasting:
> foo ILIKE 'bar'
> into:
> LOWER(foo) LIKE LOWER('bar')

In some locales those are not equivalent, I believe, or at least
shouldn't be. (What the current code actually does is a separate
question.)

> Perhaps the parser could read the former as the latter?

Not unless the equivalence can be shown to be exact, which I doubt.
In any case it's not obvious why LOWER rather than UPPER.

regards, tom lane

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Vlad Arkhipov 2012-12-29 01:36:55 Rewriter hook
Previous Message Tom Lane 2012-12-28 23:35:02 Re: enhanced error fields