How to query PostgreSQL data source using Federation Server through JDBC driver

To configure a federation to access PostgreSQL data source through JDBC wrapper, you need to provide information about data sources and objects that you want to access. Then create wrapper, server, user mapping and nickname about the tables on remote PostgreSQL data source.

Before you begin

Check the driver FOpostgresql.jar in the path $/INSTANCE_HOME/sqllib/federation/jdbc/lib.

1. Enable Federation server and restart Db2.

# db2 update dbm cfg using federated YES

# db2stop force

# db2start

2. Test the connection to the PostgreSQL data source and verify the service is started correctly.

telnet <greenplum_ip> <port>
If the connection is successful, you receive the following similar output from the command.

# telnet 9.30.166.95 5432
Trying 9.30.166.95...
Connected to 9.30.166.95.
If the connection fails, you will receive an error, please check the PostgreSQL service status.

3. Create wrapper, server, user mapping, nickname, and query the nickname. 

# connect to testdb

# create wrapper "wrapper1" library 'libdb2rcjdbc.so' options(db2_fenced 'y')

# CREATE SERVER server1 TYPE POSTGRESQL WRAPPER "wrapper1" OPTIONS (DRIVER_CLASS  'com.ibm.fluidquery.jdbc.postgresql.PostgreSQLDriver' ,DRIVER_PACKAGE  '/home/db2inst1/sqllib/federation/jdbc/lib/FOpostgresql.jar' , URL  'jdbc:ibm:postgresql://9.30.166.95:5432;DatabaseName=postgres' )

# CREATE USER MAPPING FOR PUBLIC SERVER server1 OPTIONS (REMOTE_AUTHID  'postgres' ,REMOTE_PASSWORD 'passw0rd' )
# create nickname nk1 for server1."tb11"

# select * from nk1

col_1

--------------------------

1970-11-23-12.12.12.000000

1999-12-31-12.12.12.000000

  2 record(s) selected.