Re: [GENERAL] Collation rules and multi-lingual databases

[Dennis Gearon]

I think it would be nice, and I may write it eventually, to have a 
function called:

COLLATION_VALUE( 'string', 'encoding' )

Which could be used like:

SELECT field_a, field_b
FROM table_a
GROUP BY COLLATION_VALUE( field_a )
ORDER BY COLLATION_VALUE( field_b );
or in other creative ways.

Greg Stark wrote:

Tom Lane <[EMAIL PROTECTED]> writes:

 

Greg Stark <[EMAIL PROTECTED]> writes:
   

My understanding is that the entire set of localization parameters needs to be
decided upon when the initdb is done and can never be changed later. Is that
right?
     

No, not all of them are frozen.  Unfortunately, the one you care about
(LC_COLLATE) is.  The reason for this is that it determines index
ordering for textual columns, and so changing LC_COLLATE on the fly
produces instant corrupt indexes :-(
   

Yeah, I really would be perfectly happy to have indexes be in "C" order and
have my queries have to specifically specify the sort order in the ORDER BY
clause, knowing they won't use the index.
Well, ok, not quite perfectly happy. But in this case there are no indexes on
the columns anyways so...
 

A solution for this is on the TODO list, but don't hold your breath ...
   

 



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