On 8/22/06, Alvaro Herrera <alvherre(at)commandprompt(dot)com> wrote:
> Ulrich Habel wrote:
> > Hello all,
> > had an idea of optimizing a query that may work generally.
> > In case a 'column' is indexed, following two alterations could be done
> > I think:
> > A)
> > select ... where column ~ '^Foo' --> Seq Scan
> This is not true. You can make this query use an index if you create it
> with opclass varchar_pattern_ops or text_pattern_ops, as appropiate.
> Thus you don't need any hack here.
And in the case of more general expression, like:
select ... where column ~ 'something';
Is there a way to optimise this ? (in the case where 'something' is not
a word, but a part of a word)
In response to
pgsql-performance by date
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