[Date Prev][Date Next] [Chronological] [Thread] [Top]

Re: substring index oddity

> It is quite clear in the docs that the default minimum substring indexing
> starts at 3 characters.  So the "*2" and the "*22" substring searches will
> not be using the index at all unless you've tweaked this.

No, I've made no mods.  So "*22" shouldn't be on an index, yet it's quite fast. 
That does explain why "*2" is slow though.

> BTW, if you have your loglevel up to around 256, do you see this message?
> bdb_substring_candidates: (uid) index_param failed (18)

Nope, no such messages.

> So I'm guessing that "*XXX*" is one character short index wise.  That may
> or may not be by design.

It seems that having the glob on the end of the string is perhaps related to
things being slow, although I've done so many tests I don't remember clearly.


John Madden
UNIX Systems Engineer
Ivy Tech Community College of Indiana