On 03/02/2012 08:30, Chris Travers wrote:
On Fri, Feb 3, 2012 at 12:26 AM, garry <garry@xxxxxxxxxxxxxxx>
wrote:
I have a table which holds a user name and their results in
exams. There can be multiple entries per user. I am trying to
return the last entry for each user. I can get the last entry
in the table using the order by/limit method but how would
this be applied per user. My table definition is like the
following:
gradeid serial primary key,
user text,
grade char(1),
entered timestamp,
Any help would be appreciated.
Regards
What about a combination of a common table _expression_ and a
windowing function? You ought to be able to order by your
criteria and then pull where the rowcount in the window is 1.
Unfortunately I am using a version of postgres without the windowing
functions, but that would have done the job.
Regards
Garry
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