Communication between GRASS and ODBC database for attribute management:

       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.

   DefiningtheODBCconnectionMS-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 https://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 https://www.unixodbc.org/doc/UserManual/

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

   UsingtheODBCdriver
       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.

       Communication between GRASS and ODBC database for attribute management:
       GRASS module <->                                             <-->                                                         ODBC Interface                                               <-->                                                         RDBMS

       GRASSDBMIdriverunixODBCODBCdriverPostgreSQLOracle...

       All SQL operators supported by ODBC.

db.connect,v.db.connect,unixODBCwebsite,SQLsupportinGRASSGIS

       Available at: ODBC DATABASE DRIVER source code (history)

       Accessed: Friday Apr 04 01:18:40 2025

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       © 2003-2025 GRASS Development Team, GRASS GIS 8.4.1 Reference Manual

GRASS 8.4.1                                                                                   grass-odbc(1grass)

       All SQL commands supported by ODBC.