Re: query optimization question

That looks really promising as a possibility, however I think you intended
to add a group by clause.

Terry Fielder
Network Engineer
Great Gulf Homes / Ashton Woods Homes
terry(at)greatgulfhomes(dot)com

> -----Original Message-----
> From: Masaru Sugawara [mailto:rk73(at)sea(dot)plala(dot)or(dot)jp]
> Sent: Wednesday, November 06, 2002 11:44 AM
> To: terry(at)ashtonwoodshomes(dot)com
> Cc: pgsql-sql(at)postgresql(dot)org
> Subject: Re: [SQL] query optimization question
>
>
> On Wed, 6 Nov 2002 09:01:49 -0500
> <terry(at)ashtonwoodshomes(dot)com> wrote:
>
> > If anyone can see a way to do a group by to do this, then I
> will be happy to
> > hear about it, because currently the resultset has to do a separate
> > (sequential or index) scan of the deficiencies table. The
> only way I can
> > see to do a group by would be to break out the aging categories into
> > separate queries, but that wins me nothing because each
> query then does its
> > own scan...
> >
> > The expected simplified output of this query looks like this:
> > Project <30 30-60 >=60 lot total <30
> 30-60 >=60 def total
> > X 1 2 1 4 5 10 5
> 20 (if X had 4 lots, each of 5 deficiencies)
> > Y 1 1 0 2 3 3 0
> 6 (each has eg 3 deficiencies in project Y)
> >
>
>
> The following query may be one of the ways, but I cannot
> confirm whether
> it goes well or not.
>
>
> SELECT
> project_id,
> marketing_name,
> COUNT(lots.lot_id) AS def_count,
> COUNT(CASE WHEN dt.days_old_start_date < {d '2002-10-07'}
> THEN lots.lot_id ELSE NULL END) AS
> def_count_less_30,
> COUNT(CASE WHEN dt.days_old_start_date >= {d '2002-10-07'}
> AND dt.days_old_start_date < {d
> '2002-09-07'}
> THEN lots.lot_id ELSE NULL END) AS
> def_count_30_60,
> COUNT(CASE WHEN dt.days_old_start_date >= {d '2002-09-07'}
> AND dt.days_old_start_date < {d
> '2002-08-08'}
> THEN lots.lot_id ELSE NULL END) AS
> def_count_60_90,
> COUNT(CASE WHEN dt.days_old_start_date >= {d '2002-08-08'}
> THEN lots.lot_id ELSE NULL END) AS
> def_count_greater_90,
> COUNT(DISTINCT(CASE WHEN
> dt.days_old_start_date <
> {d '2002-10-07'}
> THEN lots.lot_id ELSE NULL END ))
> AS lot_count_less_30,
> COUNT(DISTINCT(CASE WHEN
> dt.days_old_start_date >=
> {d '2002-10-07'}
> AND dt.days_old_start_date < {d
> '2002-09-07'}
> THEN lots.lot_id ELSE NULL END ))
> AS lot_count_30_60,
> COUNT(DISTINCT(CASE WHEN
> dt.days_old_start_date >=
> {d '2002-09-07'}
> AND dt.days_old_start_date < {d
> '2002-08-08'}
> THEN lots.lot_id ELSE NULL END ))
> AS lot_count_60_90,
> COUNT(DISTINCT(CASE WHEN
> dt.days_old_start_date >=
> {d '2002-08-08'}
> THEN lots.lot_id ELSE NULL END ))
> AS lot_count_greater_90,
> COUNT(DISTINCT lots.lot_id) AS lot_count
> FROM
> (SELECT * FROM deficiency_table
> WHERE assigned_supplier_id = '101690') AS dt,
> (SELECT * FROM deficiency_status,
> WHERE ds.is_outstanding) AS ds,
> (SELECT * FROM projects
> WHERE proj.division_id = 'GGH') AS proj
> lots
> WHERE
> dt.lot_id = lots.lot_id
> AND lots.division_id = proj.division_id
> AND lots.project_id = proj.project_id
> AND dt.deficiency_status_id = ds.deficiency_status_id
> AND NOT EXISTS
> (SELECT 1 FROM menu_group_projects
> WHERE menu_code = 'WA'
> AND division_id = proj.division_id
> AND project_id = proj.project_id
> AND status = 'I')
> ORDER BY proj.project_id
>
>
>
>
> Regards,
> Masaru Sugawara
>