Re: question about performance

A. Kretschmer schrieb:

>> if I have a table, the_table, with a DATE field, i'll call it 'day', and
>> I'd like to find all rows whos day falls within a given month, which of the
>> following methods is faster/costs less:
>>
>> 1.
>>
>>     SELECT * FROM the_table WHERE day LIKE '2008-01-%';
>>
>> 2.
>>
>>     SELECT * FROM the_table
>>         WHERE ( day BETWEEN '$month_begin' AND '$month_end' );
>>
>>     # where $month_begin is '2008-01-01' and $month_end is '2008-01-31';
>
> Probably the second one, but it depends if you have a propper index.
>
> Other solution: create a functional index based on date_trunc and
> rewrite your where-condition also.

Can you give an example?

Greetings,
Torsten