Ron Mayer wrote:
> Bruce Momjian wrote:
> > Oleg Bartunov wrote:
> >> What is a basis of your assumption ? In my opinion, it's very limited
> >> use of text search, because it doesn't supports ranking. For 4-5 years
> >> of tsearch2 usage I never used it and I never seem in mailing lists.
> >> This is very user-oriented feature and we could probably ask 
> >> -general people for their opinion.
> I think I asked about this kind of usage a couple years back;
> and Oleg pointed out other reasons why it wasn't as good an
> idea too.
> The particular question I had asked why the functional index was
> slower than maintaining the extra column; with the explanation
> that the lossy index having to call the function (including
> parsing, dictionary lookup, etc) for re-checking the data made
> it inadvisable to avoid the extra column anyway.
> > I doubt 'general' is going to understand the details of merging this
> > into the backend.  I assume we have enough people on hackers to decide
> > this.
> > 
> > Are you saying the majority of users have a separate column with a
> > trigger?
> I think so.   At least when I was using it in 2005 the second
> column with the trigger was faster than using a functional index.

OK, it is good you measured it.  I wonder how GIN would behave because
it is not lossy.

> >> We need more feedback from users.
> > 
> > Well, I am waiting for other hackers to get involved, but if they don't,
> > I have to evaluate it myself on the email lists.
> Personally, I think documentation changes would be an OK way to
> to handle it.   Something that makes it extremely clear to the
> user the advantages of having the extra column and the risks
> of avoiding them.

Sure, but you have make sure you use the right configuration in the
trigger, no?  Does the tsquery have to use the same configuration?

  Bruce Momjian  <[EMAIL PROTECTED]>

  + If your life is a hard drive, Christ can be your backup. +

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