On 11/07/2014 12:06 AM, Vlad Arkhipov wrote:
It was just a minimal example. The real query looks like this.
select *
from commons.financial_documents fd
where fd.creation_time < '2011-11-07 10:39:07.285022+08'
or (fd.creation_time = '2011-11-07 10:39:07.285022+08' and
fd.financial_document_id < 100)
order by fd.creation_time desc
limit 200
I need to rewrite it in the way below to make Postgres use the index.
select *
from commons.financial_documents fd
where fd.creation_time <= '2011-11-07 10:39:07.285022+08'
and (
fd.creation_time < '2011-11-07 10:39:07.285022+08'
or (fd.creation_time = '2011-11-07 10:39:07.285022+08' and
fd.financial_document_id < 100)
)
order by fd.creation_time desc
limit 200
First, please do not top-post on the PostgreSQL lists. See
<http://idallen.com/topposting.html>
Second, the last test for fd.creation_time in your query seems
redundant. Could you not rewrite it as something this?:
where fd.creation_time <= '2011-11-07 10:39:07.285022+08'
and (fd.creation_time < '2011-11-07 10:39:07.285022+08'
or fd.financial_document_id < 100)
cheers
andrew
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