Igor Tandetnik wrote:
>
> pierr wrote:
>> Following 2 statements took 400ms to be excuted on a 350M MIPS CPU
>> and it is a memory database:
>>
>> "DELETE FROM tblEvent_type WHERE eguid in (SELECT rowid FROM
>> tblEvent_basic WHERE sguid=11);";
>> "DELETE FROM tblEvent_group WHERE eguid in (SELECT rowid FROM
>> tblEvent_basic WHERE sguid=11);";
>> (An index has been created on tblEvent_group(eguid) , no other index
>> so far.)
>
> You might benefit from an index on tblEvent_basic(sguid). An index on
> tblEvent_group(eguid) may actually hurt performance.
>
>
Igor,
This is really what I found. Why an index on tblEvent_group(eguid) hurted
the performance?
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