Re: BUG #5781: unaccent() function should be marked IMMUTABLE

On Wed, Dec 22, 2010 at 8:45 PM, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> Tom Lane wrote:
>> "Grant Hutchins and Peter Jaros" <grant(at)pivotallabs(dot)com> writes:
>> > The unaccent(text) function supplied by contrib/unaccent is marked VOLATILE.
>> > This prevents it from being used in indexes. We believe that the function
>> > meets the requirements to be marked IMMUTABLE.
>>
>> No, it most certainly doesn't.  It depends on the behavior of a
>> dictionary that it has no hard-wired connection to, so the specific
>> behavior of the dictionary is uncertain.  Even if you're willing to
>> assume that the dictionary being used is the one defined by this
>> module, that dictionary depends on external configuration files
>> which are easily changeable.
>>
>> Arguably it'd be reasonable to change the function's marking from
>> volatile to stable, but that's not going to be enough to allow use in
>> indexes.
>
> So, should we change unaccent() from VOLATILE to STABLE?

Sounds like it, but it doesn't sound like it will help much. :-(

--
Robert Haas
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