RE: [HACKERS] Progress report on locale safe LIKE indexing

[Hiroshi Inoue]

> -----Original Message-----
> From: Peter Eisentraut [mailto:[EMAIL PROTECTED]]
> 
> Hiroshi Inoue writes:
> 
> > Isn't 'a' LIKE 'A' if 'a' = 'A' ?
> 
> Yes.  But 'a' <> 'A'.

Please look at my first question.
   This depends on the assumption that '=' is equivalent in
   any locale. Is it guaranteed ?
   For example, ( 'a' = 'A' ) isn't allowed in any locale ?. 

And your answer was
   The whole point here is not to rely on '='. 

Clearly your theory depends on the assumption that
   If a = b in some locale then a = b in ASCII locale.

And where does 'a' <> 'A' come from ?
The definition of '=' is a part of collating sequence.

> 
> > LIKE seems to use the collating sequence.
> 
> No.  The collating sequence defines the order of all possible strings.
> LIKE doesn't order anything.

Again where does it come from ?

regards,
Hiroshi Inoue

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