On Mon, Apr 20, 2009 at 7:55 AM, Rafael Domiciano
<rafael.domiciano@gmail.com> wrote:
> Hello People,
>
> I have initiated a work to review the sqls of our internal software.
> Lot of them he problem are about sql logic, or join with table unecessary,
> and so on.
> But software has lot of sql with date, doing thinks like:
> [..]
> date >= '2009-04-01' AND
> date <= '2009-04-15'
> [..]
>
> Redoing the SQL with fix date (date = '2009-04-01') o cost in explain always
> still about 200 or less. But with a period the cost is high, about 6000 or
> more.
Yep. Because you'll be getting more rows. More rows == more cost. TANSTAAFL.