Re: using CURSOR with PHP

On Sun, 2002-05-19 at 13:07, Keary Suska wrote:
>
> > For more complex queries, however, the plans are less likely to differ
> >
> Actually, as you can see with my examples above, the reverse is true, as the
> simple query produced the same plan. The more complex the query, the more
> choices the optimizer has for picking the best case, which unfortunately is
> not always the truly best case.

No, I meant _complex_ plans:

pcno=# explain select * from vwmbradr where centre_id = 56;
NOTICE:  QUERY PLAN:

Subquery Scan vwmbradr  (cost=636.68..636.68 rows=1 width=418)
  ->  Sort  (cost=636.68..636.68 rows=1 width=418)
        ->  Nested Loop  (cost=0.00..636.67 rows=1 width=418)
              ->  Nested Loop  (cost=0.00..630.67 rows=1 width=340)
                    ->  Nested Loop  (cost=0.00..624.68 rows=1
width=254)
                          ->  Index Scan using primary_centre_id_index
on constituents  (cost=0.00..622.35 rows=1 width=212)
                          ->  Seq Scan on centres  (cost=0.00..1.59
rows=59 width=42)
                    ->  Index Scan using constituents_pkey on
constituents  (cost=0.00..5.98 rows=1 width=86)
              ->  Index Scan using constituents_pkey on constituents
(cost=0.00..5.98 rows=1 width=78)

EXPLAIN
pcno=# explain select * from vwmbradr where centre_id = 56 limit 1;
NOTICE:  QUERY PLAN:

Limit  (cost=636.68..636.68 rows=1 width=418)
  ->  Subquery Scan vwmbradr  (cost=636.68..636.68 rows=1 width=418)
        ->  Sort  (cost=636.68..636.68 rows=1 width=418)
              ->  Nested Loop  (cost=0.00..636.67 rows=1 width=418)
                    ->  Nested Loop  (cost=0.00..630.67 rows=1
width=340)
                          ->  Nested Loop  (cost=0.00..624.68 rows=1
width=254)
                                ->  Index Scan using
primary_centre_id_index on constituents  (cost=0.00..622.35 rows=1
width=212)
                                ->  Seq Scan on centres
(cost=0.00..1.59 rows=59 width=42)
                          ->  Index Scan using constituents_pkey on
constituents  (cost=0.00..5.98 rows=1 width=86)
                    ->  Index Scan using constituents_pkey on
constituents  (cost=0.00..5.98 rows=1 width=78)

EXPLAIN


:-)


Cheers,
                    Andrew.
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