ODBC DATABASE DRIVER

       Communication between GRASS and ODBC database for attribute management:

       GRASS module <->                                             <-->                                                         ODBC Interface                                               <-->                                                         RDBMS

       GRASS                                                        DBMI driver                                                  unixODBC                                                     ODBC driver                                                  PostgreSQL

       Oracle

       ...

Supported SQL commands

       All SQL commands supported by ODBC.

Operators available in conditions

       All SQL operators supported by ODBC.

EXAMPLE

       In  this  example we copy the dbf file of a SHAPE map into ODBC, then connect GRASS to the
       ODBC DBMS. Usually the table will be already present in the DBMS.

   Defining the ODBC connection
   MS-Windows
       On MS-Windows, in order to be able to connect, the ODBC connection needs to be  configured
       using  dedicated  tools  (tool called "ODBC Data Source Administrator") and give a name to
       that connection. This name is then used as database name when accessing from a client  via
       ODBC.

   Linux
       Configure ODBC driver for selected database (manually or with ’ODBCConfig’).  ODBC drivers
       are defined in /etc/odbcinst.ini. Here an example:

        [PostgreSQL]
        Description     = ODBC for PostgreSQL
        Driver          = /usr/lib/libodbcpsql.so
        Setup           = /usr/lib/libodbcpsqlS.so
        FileUsage       = 1

       Create DSN (data source name). The DSN is used as database name in db.*  modules. Then DSN
       must  be  defined in $HOME/.odbc.ini (for this user only) or in /etc/odbc.ini for (for all
       users) [watch out for the database name which appears twice and also  for  the  PostgreSQL
       protocol version]. Omit blanks at the beginning of lines:

        [grass6test]
        Description             = PostgreSQL
        Driver                  = PostgreSQL
        Trace                   = No
        TraceFile               =
        Database                = grass6test
        Servername              = localhost
        UserName                = neteler
        Password                =
        Port                    = 5432
        Protocol                = 8.0
        ReadOnly                = No
        RowVersioning           = No
        ShowSystemTables        = No
        ShowOidColumn           = No
        FakeOidIndex            = No
        ConnSettings            =
       Configuration of an DSN without GUI is described on http://www.unixodbc.org/odbcinst.html,
       but odbc.ini and .odbc.ini may be created by the ’ODBCConfig’ tool. You  can  easily  view
       your   DSN   structure   by   ’DataManager’.   Configuration  with  GUI  is  described  on
       http://www.unixodbc.org/doc/UserManual/

       To find out about your PostgreSQL protocol, run:
       psql -V

   Using the ODBC driver
       Now create a new database if not yet existing:

       db.createdb driver=odbc database=grass6test

       To store a table ’mytable.dbf’ (here: in current directory) into PostgreSQL through  ODBC,
       run:

       db.connect driver=odbc database=grass6test
       db.copy from_driver=dbf from_database=./ from_table=mytable \
               to_driver=odbc to_database=grass6test to_table=mytable

       Next link the map to the attribute table (now the ODBC table is used, not the dbf file):

       v.db.connect map=mytable.shp table=mytable key=ID \
                    database=grass6test driver=odbc
       v.db.connect -p

       Finally a test: Here we should see the table columns (if the ODBC connection works):
       db.tables -p
       db.columns table=mytable

       Now the table name ’mytable’ should appear.
       Doesn’t work? Check with ’isql <databasename>’ if the ODBC-PostgreSQL connection is really
       established.

       Note that you can also connect mySQL, Oracle etc. through ODBC to GRASS.

       You can also check the vector map itself concerning a current link to a table:

       v.db.connect -p mytable.shp

       which should print the database connection through ODBC to the defined RDBMS.

SEE ALSO

        db.connect, v.db.connect, unixODBC web site, SQL support in GRASS GIS

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       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual