On 12-Nov-07, at 9:56 AM, Alvaro Herrera wrote:
> Dave Cramer wrote:
>> In order to get like queries to use an index with database
>> initialized with
>> a UTF-8 character set I added a unique index to a table with a
>> This table already had a unique constraint on the column so I
>> dropped the
>> unique constraint.
>> I can't give exact measurements however this caused my application
>> to slow
>> down considerably.
>> The only thing I can figure is that the varchar_pattern_ops
>> operator is
>> significantly slower ???
>> Is there some other piece of the puzzle to fill in ?
> Well, AFAIK the index with varchar_pattern_ops is used for LIKE
> whereas the other one is going to be used for = queries. So you
> need to
> keep both indexes.
You would be correct, thanks for the quick answer.
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