On 01/22/2013 09:21 AM, rudi wrote:
On Tue, Jan 22, 2013 at 3:04 PM, Merlin Moncure <mmoncure@xxxxxxxxx
<mailto:mmoncure@xxxxxxxxx>> wrote:
let's see the query -- it's probably written in such a way so as to
not be able to be optimized through CE.
The query is pretty simple and standard, the behaviour (and the plan)
is totally different when it comes to a partitioned table.
Partioned table query => explain analyze SELECT "sb_logs".* FROM
"sb_logs" WHERE (device_id = 901 AND date_taken = (SELECT
MAX(date_taken) FROM sb_logs WHERE device_id = 901));
And there you have it. Constraint exclusion does not work in cases like
this. It only works with static expressions (such as a literal date in
this case).
cheers
andrew
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