Re: optimize/cleanup SQL

Brandon Metcalf <brandon@geronimoalloys.com> writes:
> For some reason this doesn't give me satisfaction that it's written
> optimally, but I haven't found another way.

>   SELECT round(CAST ((EXTRACT(EPOCH FROM clockout)
>               -EXTRACT(EPOCH FROM clockin))/3600 AS NUMERIC),2) AS hours
>     FROM timeclock;

> The clockin and clockout columns are of type timestamp.

timestamp, or timestamptz?  extract(epoch from timestamptz) is really
quite a cheap operation; there's no need to worry about performance
in that case.  If what's bothering you is ugliness, encapsulate this
as an inlineable SQL function.

            regards, tom lane