Re: like/ilike improvements

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andrew Dunstan <andrew@dunslane.net>
Cc: andrew@supernews.com, pgsql-hackers@postgresql.org
Date: 2007-05-25T01:26:19Z
Lists: pgsql-hackers
Andrew Dunstan <andrew@dunslane.net> writes:
> However, I have just about convinced myself that we don't need 
> IsFirstByte for matching "_" for UTF8, either preceded by "%" or not, as 
> it should always be true. Can anyone come up with a counter example?

You have to be on a first byte before you can meaningfully apply
NextChar, and you have to use NextChar or else you don't count
characters correctly (eg "__" must match 2 chars not 2 bytes).

			regards, tom lane