Hengky Liwandouw <hengkyliwandouw@gmail.com> wrote:
> where jualid is not null
> and extract(year from tanggal)='2013')
> But the problem is : when i change the where clause to :
>
> where jualid is not null or returjualid is not null
> and extract(year from tanggal)='2013')
>
> (there is additional or returjualid is not null,) the query needs
> 56 second to display the result.
Before worrying about the run time, I would worry about whether you
are getting the results you expect. That will be interpreted as:
where jualid is not null
or (returjualid is not null and extract(year from tanggal) = '2013')
... not:
where (jualid is not null or returjualid is not null)
and extract(year from tanggal) = '2013'
AND has higher priority than OR; so if you want to limit by year
from tanggal even when jualid is not null, you must use
parentheses.
--
Kevin Grittner
EDB: http://www.enterprisedb.com
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