The PostgreSQL database must have logical replication enabled. Also, each source table must have a primary key. Most PostgreSQL data types are supported.

PowerExchange retrieves change data from a PostgreSQL logical replication slot named pwx_repl, which uses a PowerExchange-installed plugin named pwx_decode.dll or pwx_decode.so. The replication slot is generated for PowerExchange use when capture processing runs. PowerExchange stores the change data in the

replication store table

in the source database. PowerExchange automatically creates the replication store table if it does not already exist during capture processing. Alternatively, you can manually create the table by using the DDL statements in Manually Creating the Replication Store Table.

PowerExchange requires the DataDirect ODBC driver for PostgreSQL to retrieve source metadata from the PostgreSQL database server. The PowerExchange installation delivers this ODBC driver in the

root_install_directory

\ODBC

v.r

\Drivers folder on Windows or

root_install_directory

/ODBC

v.r

/lib directory on Linux.

Use of the PowerExchange Logger for Linux, UNIX, and Windows is optional. If you use the PowerExchange Logger, the Logger extracts change data from the replication store table and stores the data in its log files.

When a CDC session runs, PowerExchange works with the PowerExchange Client for PowerCenter (PWXPC) to extract change records from the real-time change stream or from the PowerExchange Logger logs and to transmit the data to one or more targets.