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       grass-pg - PostgreSQL driver

       PostgreSQL  driver PostgreSQL DB driver in GRASS The DB (database) driver name in GRASS is

Creating a PostgreSQL database

       A new database is created with createdb, see the PostgreSQL manual for details.

Connecting GRASS to PostgreSQL

       # example for connecting to a PostgreSQL server:
       db.connect driver=pg database=",dbname=mydb"
       # password is asked interactively if not specified:
       db.login user=myname [pass=secret]
       db.connect -p
       db.tables -p

Supported SQL commands

       All SQL commands supported by PostgreSQL.  It's not possible to use C-like  escapes  (with
       backslash like \n etc) within the SQL syntax.

Operators available in conditions

       All SQL operators supported by PostgreSQL.

Adding an unique ID column

       Import  vector  module  require an unique ID column which can be generated as follows in a
       PostgreSQL table:
       db.execute sql="ALTER TABLE mytable ADD ID integer"
       db.execute sql="CREATE SEQUENCE mytable_seq"
       db.execute sql="UPDATE mytable SET ID = nextval('mytable_seq')"
       db.execute sql="DROP SEQUENCE mytable_seq"

Attribute import into PostgreSQL

       CSV import into PostgreSQL:
       \h copy
       COPY t1 FROM 'filename' USING DELIMITERS ',';

Geometry import from PostgreSQL table into GRASS creates a new vector (points) map from a database  table  containing  coordinates.
       See here for examples.

PostGIS: PostgreSQL with vector geometry

       PostGIS: adds geographic object support to PostgreSQL.

   Example: Import from PostGIS
       In an existing PostGIS database, create the following table:
       CREATE TABLE test
        id serial NOT NULL,
        mytime timestamp DEFAULT now(),
        text varchar,
        wkb_geometry geometry,
        CONSTRAINT test_pkey PRIMARY KEY (id)
       ) WITHOUT OIDS;
       # insert value
       INSERT INTO test (text, wkb_geometry)
        VALUES ('Name',geometryFromText('POLYGON((600000 200000,650000
        200000,650000 250000,600000 250000,600000 200000))',-1));
       # register geometry column
       select AddGeometryColumn ('postgis', 'test', 'geometry', -1, 'GEOMETRY', 2);
        GRASS can import this PostGIS polygon map as follows: dsn="PG:host=localhost dbname=postgis user=neteler" layer=test \
                output=test type=boundary,centroid test -t test

   Geometry Converters
                     PostGIS with shp2pgsql:
                     shp2pgsql -D lakespy2 lakespy2 test > lakespy2.sql

                     e00pg: E00 to PostGIS filter, see also

                     GDAL/OGR  ogrinfo and ogr2ogr: GIS vector format converter and library, e.g.
                     ArcInfo or SHAPE to PostGIS.
                     ogr2ogr -f "PostgreSQL" shapefile ??


        db.connect, db.execute

       Database management in GRASS GIS
       Help pages for database modules
       SQL support in GRASS GIS


                     PostgreSQL web site

                     pgAdmin graphical user interface

                     GDAL/OGR PostgreSQL driver documentation

       Last changed: $Date: 2012-09-12 06:22:50 -0700 (Wed, 12 Sep 2012) $
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