David E. Wheeler wrote:
> On Jul 3, 2008, at 00:19, Teodor Sigaev wrote:
>
>>> Hash opclass is 5-times simpler that btree one :)
>>
>> CREATE FUNCTION citext_hash(mchar)
>> RETURNS int4
>> AS 'MODULE_PATHNAME'
>> LANGUAGE C IMMUTABLE RETURNS NULL ON NULL INPUT;
>>
>> CREATE OPERATOR CLASS citext_ops
>> DEFAULT FOR TYPE mchar USING hash AS
>> OPERATOR 1 = (citext, citext),
>> FUNCTION 1 citext_hash(citext);
>
> Thanks. What would citext_hash() look like? I don't see a text_hash() to
> borrow from anywhere in src/.
See hash_any(). I assume the difficulty is making sure that
hash("FOO") = hash("foo") ...
--
Alvaro Herrera http://www.CommandPrompt.com/
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