ace@aced:/home/shared/srcsAced/gdalautotest_trunk$ ipython
Python 2.5.2 (r252:60911, Jan  4 2009, 21:59:32) 
In [1]: import ogr/usr/local/lib/python2.5/site-packages/osgeo/gdal.py:81: DeprecationWarning: ogr.py was placed in a namespace, it is now available as osgeo.ogr
In [2]: import gdal
In [3]: pg_ds = ogr.Open( 'PG:dbname=autotest password=aced1234', update = 1 )
In [4]: pg_dr = ogr.GetDriverByName( 'PostgreSQL' )

In [9]: sql_lyr = pg_ds.ExecuteSQL('SELECT postgis_version()')
In [10]: tRes = sql_lyr.next()

In [14]: tRes.items()
Out[14]: {'postgis_version': '1.5 USE_GEOS=1 USE_PROJ=1 USE_STATS=1 USE_LIBXML2=1'}

In [16]: pg_ds.ReleaseResultSet(sql_lyr)

In [22]: pg_lyr = pg_ds.CreateLayer( 'tpoly',options = [ 'DIM=3' ] )

In [23]: pg_lyr.TestCapability(ogr.OLCFastSpatialFilter)
Out[23]: True

In [24]: pg_lyr.TestCapability(ogr.OLCFastGetExtent)
Out[24]: True

In [25]: pg_lyr.TestCapability(ogr.OLCRandomRead)
Out[25]: True

In [26]: pg_lyr.TestCapability(ogr.OLCFastFeatureCount)
Out[26]: True

In [28]: pg_lyr.TestCapability(ogr.OLCFastSetNextByIndex)
Out[28]: True

In [29]: try:
   ....:     ogr.OLCStringsAsUTF8
   ....:     if not pg_lyr.TestCapability(ogr.OLCStringsAsUTF8):
   ....:         print 'fail'
   ....:         
   ....: except:
   ....:     pass
   ....: 
Out[29]: 'StringsAsUTF8'

In [32]: def quick_create_layer_def( lyr, field_list):
   ....:     for field in field_list:
   ....:         name = field[0]
   ....:         if len(field) > 1:
   ....:             type = field[1]
   ....:         else:
   ....:             type = ogr.OFTString
   ....:         field_defn = ogr.FieldDefn( name, type )
   ....:         if len(field) > 2:
   ....:             field_defn.SetWidth( int(field[2]) )
   ....:         if len(field) > 3:
   ....:             field_defn.SetPrecision( int(field[3]) )
   ....:         lyr.CreateField( field_defn )
   ....:         field_defn.Destroy()
   ....:         
   ....: 

In [33]: quick_create_layer_def( pg_lyr,
   ....: [ ('AREA', ogr.OFTReal),
   ....: ('EAS_ID', ogr.OFTInteger),
   ....: ('PRFEDEA', ogr.OFTString),
   ....: ('SHORTNAME', ogr.OFTString, 8) ] )
ERROR 1: ALTER TABLE "tpoly" ADD COLUMN "area" FLOAT8
ERROR:  relation "tpoly" does not exist

ERROR 1: ALTER TABLE "tpoly" ADD COLUMN "eas_id" INTEGER
ERROR:  relation "tpoly" does not exist

ERROR 1: ALTER TABLE "tpoly" ADD COLUMN "prfedea" VARCHAR
ERROR:  relation "tpoly" does not exist

ERROR 1: ALTER TABLE "tpoly" ADD COLUMN "shortname" CHAR(8)
ERROR:  relation "tpoly" does not exist


In [34]: pg_ds.CreateLayer( 'tpoly',options = [ 'DIM=3' ] )
ERROR 1: Layer tpoly already exists, CreateLayer failed.
Use the layer creation option OVERWRITE=YES to replace it.

## at this point, there is one schema, public
## and the db looks like this
autotest=# \d
             List of relations
 Schema |       Name        | Type  | Owner 
--------+-------------------+-------+-------
 public | geography_columns | view  | ace
 public | geometry_columns  | table | ace
 public | spatial_ref_sys   | table | ace
(3 rows)