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#1 (**permalink**) 04-18-2008, 11:04 AM

> Alexandre Leclerc wrote:
> Sorry for jumping in on this thread so late -- I haven't been able to
> select * from crosstab(
> 'select product_id, department_id, req_time
> from product_department_time order by 1',
> 'select ''A'' union all select ''C'' union all select ''D'''
> ) as (product_id int, a int, c int, d int);

I forgot you could do this...This would certainly be easier than parsing
array values returned from array_accum. It will probably be faster as
well...but with the array approach the query would not have to be
modified each time a new department was added. That said, a crosstab
based query could be built easily enough from a department query on the
client and then you have the best of both worlds.

Merlin

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#2 (**permalink**) 04-18-2008, 11:04 AM

On Fri, 4 Feb 2005 12:48:43 -0500, Merlin Moncure
<merlin.moncure@rcsonline.com> wrote:
> > Alexandre Leclerc wrote:
> > Sorry for jumping in on this thread so late -- I haven't been able to
> > select * from crosstab(
> > 'select product_id, department_id, req_time
> > from product_department_time order by 1',
> > 'select ''A'' union all select ''C'' union all select ''D'''
> > ) as (product_id int, a int, c int, d int);
>
> I forgot you could do this...This would certainly be easier than parsing
> array values returned from array_accum. It will probably be faster as
> well...but with the array approach the query would not have to be
> modified each time a new department was added. That said, a crosstab
> based query could be built easily enough from a department query on the
> client and then you have the best of both worlds.

Hello Merlin,

Well, I'm glad because with all this i've learn a lot of new things.

Finally, the crosstab solution is very fast and is simple for me to
use. I get my super-bug-jumbo-dbkiller-query run in about 210ms
(seeking many tables and so). I had a score of 2480ms before. (This is
a much more complex query; the cross table thing had to be included in
this one.) This is much better!

In all, thanks for your help. Regards.

--
Alexandre Leclerc

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