Re: Possible solution for LIKE optimization

Peter Eisentraut <peter_e@gmx.net> writes:
> Tom Lane writes:
>> On the other hand, LIKE *is* multibyte aware.  So the hypothetical
>> non-locale-aware comparison operators would need to be aware of
>> multibyte character sets even though not aware of locale.  And the
>> "add one" operator that we postulated for the LIKE index optimization
>> needs to be able to increment a multibyte character.

> Both of these are not hard if you know how strcmp operates.  It would also
> be irrelevant whether "add one" to a multibyte character yields another
> valid multibyte character.  strcmp doesn't care.

I imagine we can come up with a definition that makes LIKE optimization
work.  I was wondering more about Hiroshi's implied question: would such
an index have any use for sorting?  Or would the induced sort order (on
multibyte character sets) look too weird to be of any use?
        regards, tom lane