Re: [gnome-db] postgresql provider performance

[Mark Johnson <mrj001 shaw ca>]

Mark Johnson wrote:
> Vivien Malerba wrote:
>   
> > On Jan 30, 2008 4:04 PM, Mark Johnson <mrj001 shaw ca> wrote:
> >   
> >     
> > > But what information does it provide?  Here is a sample session from psql:
> > > issue001_db=# \d+ slots
> > >                          Table "public.slots"
> > >       Column       |          Type          | Modifiers | Description
> > > -------------------+------------------------+-----------+-------------
> > >  slot_id           | integer                | not null  |
> > >  obj_guid          | character(32)          | not null  |
> > >  name              | character varying(500) | not null  |
> > >  slot_type         | integer                | not null  |
> > >  int64_val         | bigint                 |           |
> > >  string_val        | character varying(500) |           |
> > >  double_val        | bigint                 |           |
> > >  timespec_val      | date                   |           |
> > >  guid_val          | character(32)          |           |
> > >  numeric_val_num   | bigint                 |           |
> > >  numeric_val_denom | bigint                 |           |
> > > Indexes:
> > >     "slots_pkey" PRIMARY KEY, btree (slot_id)
> > > Has OIDs: no
> > >
> > > issue001_db=# SELECT 1 FROM pg_catalog.pg_class c,
> > > pg_catalog.pg_constraint c2, pg_catalog.pg_attribute a WHERE c.relname =
> > > 'slots' AND c.oid = c2.conrelid and a.attrelid = c.oid and c2.contype =
> > > 'P' and c2.conkey[1] = a.attnum and a.attname = 'slot_id';
> > >  ?column?
> > > ----------
> > > (0 rows)
> > >
> > > There is not a single row returned by this query.  'slot-id' is the
> > > primary key column, which seems to be something this query might be
> > > looking for.  Does this possibly behave differently in an older version
> > > of PostgreSQL?  I am using 8.2.6.
> > >     
> > >       
> > I believe the information is in the existence of a row returned or no.
> >   
> >     
> The c2.contype='P' test checks if the column is a primary key.  This 
> alternates with checking the columns for a unique key ('u').  However, 
> the query is returning zero rows regardless of the presence or absence 
> of a primary or unique key.  In the above instance, the column is a 
> primary key as shown by the \d+ command.  When I tried columns that are 
> not primary keys, they return the same results.  I believe, therefore, 
> that there is a problem with this query.
>   
Found the problem. See bug513543:
http://bugzilla.gnome.org/show_bug.cgi?id=513543

The 'P' should be 'p'.

Mark