grass-pg(1)

1grass-pg(1)                   Grass User's Manual                  grass-pg(1)
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5PostgreSQL driver in GRASS The driver name is 'pg'.
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Creating a PostgreSQL database

8       A  new  database  is created with 'createdb', see the PostgreSQL manual
9       for details.
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Connecting GRASS to PostgreSQL

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13       # example for connecting to a PostgreSQL server:
14       db.connect driver=pg database="host=myserver.itc.it,dbname=mydb"
15       db.login user=myname pass=secret
16       db.connect -p
17       db.tables -p
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Supported SQL commands

21       All SQL commands supported by PostgreSQL.
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Operators available in conditions

24       All SQL operators supported by PostgreSQL.
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Adding an unique ID column

27       Import vector module require an unique ID column which can be generated
28       as follows in a PostgreSQL table:
29       echo "
30        ALTER TABLE mytable ADD ID integer;
31        CREATE SEQUENCE mytable_seq;
32        UPDATE mytabe SET ID = nextval('mytable_seq');
33        DROP SEQUENCE mytable_seq;
34       " | db.execute
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Attribute Converters

38       CSV import into PostgreSQL:
39       \h copy
40       COPY t1 FROM 'filename' USING DELIMITERS ',';
41        pg2xbase: DBF to PostgreSQL converter.
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PostGIS: PostgreSQL with vector geometry

44       PostGIS: adds geographic object support to PostgreSQL.
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46   Example: Import from PostGIS
47       In an existing PostGIS database, create the following table:
48       CREATE TABLE test
49       (
50        id serial NOT NULL,
51        mytime timestamp DEFAULT now(),
52        text varchar,
53        wkb_geometry geometry,
54        CONSTRAINT test_pkey PRIMARY KEY (id)
55       ) WITHOUT OIDS;
56       # insert value
57       INSERT INTO test (text, wkb_geometry)
58        VALUES ('Name',geometryFromText('POLYGON((600000 200000,650000
59        200000,650000 250000,600000 250000,600000 200000))',-1));
60       # register the table with geometry
61       select  AddGeometryColumn  ('postgis',  'test', 'geometry', -1, 'GEOME‐
62       TRY', 2);
63        GRASS can import this PostGIS polygon map as follows:
64       v.in.ogr dsn="PG:host=localhost dbname=postgis user=neteler" layer=test
65       \
66                output=test type=boundary,centroid
67       v.db.select test
68       v.info -t test
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71   Geometry Converters
72                     PostGIS with shp2pgsql:
73                     shp2pgsql -D lakespy2 lakespy2 test > lakespy2.sql
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75                     e00pg: E00 to PostGIS filter, see also v.in.e00.
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77                     GDAL/OGR ogrinfo and ogr2ogr: GIS vector format converter
78                     and library, e.g. ArcInfo or SHAPE to PostGIS.
79                     ogr2ogr -f "PostgreSQL" shapefile ??
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