Re: [GENERAL] Slow lookups on dates? Or something else?

On Mon, 25 Oct 1999, Aaron J. Seigo wrote:

> hi...

> my experience has been that this:
>
>    select date_time_field::date from table_name;
>
> is much faster than:
>
>   select date_trunc('day',date) from table_name;
>

Yes, date_trunc() is comlicated routine, this func. must internal parse and
search your 'day' - it is slowly. (.. instead of datetime_date() which make
date from full DateTime only.)

                            Zakkr

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