[Gdal-dev] PG-Driver supporting no views?

[Frank Warmerdam]

Carl Anderson wrote:
>                  "DECLARE mycursor CURSOR for "
>                  "SELECT relname FROM pg_class "
>                  "WHERE (relkind in ('r','v') AND relname !~ '^pg'" );

Carl,

Cool, thats pretty easy. I will commit this change.

> The current method scans and describes every table in the database. This 
> can take a very long time to do.  I have 2000+ tables and the 
> initialization of the OGR Pg driver takes almost a minute.  From a 
> practical standing that precludes my using in user interfaces.

My approach to this has varied from RDBMS to RDBMS.  For the ODBC driver,
it is possible to optionally include a list of tables that you would like
to be represented in the layer list in the datasource name.  For the Oracle
link I only treat spatial tables (those in the equivelent to the GEOMETRY_COLUMNS
table) as layers.  The issue of supporting tables according to schemas has
also been raised.

I hope to provide several options in the postgres/postgis driver in the
relatively near future - perhaps the next month or two.

An underlying problem though is the OGR model where opening a datasource
results in identifying all layers and collecting schema information
for them all.  I should have set things up so that you could get the
list of layer names without the layer objects having to be fully populated
(as they are now).  Perhaps I will rectify this in some fashion when I
restructure OGR drivers to merge more closely with GDAL drivers.

Best regards,

-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent