Re: Full text search - query plan? PG 8.4.1

Scott Marlowe wrote:
> On Fri, Oct 23, 2009 at 2:32 PM, Jesper Krogh <jesper(at)krogh(dot)cc> wrote:
>> Tom Lane wrote:
>>> Jesper Krogh <jesper(at)krogh(dot)cc> writes:
>>>> Tom Lane wrote:
>>>>> ... There's something strange about your tsvector index. Maybe
>>>>> it's really huge because the documents are huge?
>>>> huge is a relative term, but length(ts_vector(body)) is about 200 for
>>>> each document. Is that huge?
>>> It's bigger than the toy example I was trying, but not *that* much
>>> bigger. I think maybe your index is bloated. Try dropping and
>>> recreating it and see if the estimates change any.
>> I'm a bit reluctant to dropping it and re-creating it. It'll take a
>> couple of days to regenerate, so this should hopefully not be an common
>> situation for the system.
>
> Note that if it is bloated, you can create the replacement index with
> a concurrently created one, then drop the old one when the new one
> finishes. So, no time spent without an index.

Nice tip, thanks.

>> It is build from scratch using inserts all the way to around 10m now,
>> should that result in index-bloat? Can I inspect the size of bloat
>> without rebuilding (or similar locking operation)?
>
> Depends on how many lost inserts there were. If 95% of all your
> inserts failed then yeah, it would be bloated.

Less than 10.000 I'd bet, the import-script more or less ran by itself
the only failures where when I manually stopped it to add some more code
in it.

--
Jesper