SQL/DataSynchronization Facility: Product Summary

The SQL/Data Synchronization Facility (SQL/DSF) assists DB2/VM database administrators in managing distributed database environments. In such environments, it must be ensured that the distributed tables remain in a consistent state. The following SQL/DSF facilities help database administrators in achieving this goal:
Synchronization  Propagates changes performed on DB2/VM tables to other databases.
Transfer Transfers tables between different databases.
Compare Compares tables in different databases.
Conditional transfer Transfers a table to the target database, when a table compare results in mismatch.

All SQL/DSF functions are performed from the VM/ESA DB2/VM environment. They operate:

SQL/DSF functions can be invoked : TABLE SYNCHRONIZATION

Since SQL/DSF uses the captured statement for synchronization and not the DB2/VM log, an SQL statement that alters multiple rows will be synchronized in a single transaction. The static synchronization method of SQL/DSF is considerably faster than dynamic synchronization, commonly used by synchronization software. As a result, throughput of synchronization will be comparable to that of the SQL statements in the originating applications.

Synchronization User Exit

If requested, SQL/DSF will invoke a user exit before applying the source statements to the target database. The exit can modify the statement text or take any other appropriate action.


The transfer function copies all rows of a designated table to the target table in another database. At the user's choice, transfer will replace or append to the target. The transfer is performed using CMS workunits: no disk or tape storage is required during the operation.


The function compares all rows of a named table with the table in the designated target database and prints the contents of the mismatching rows.


The conditional transfer function is a combination of the compare and the transfer functions. A conditional transfer compares both tables and initiates a transfer when the compare results in a mismatch.


SQL/DSF provides the SQLDSFS Scheduler program to assist an installation in setting up a DataSync Server environment. Using the Scheduler, most synchronization tasks can be automated. The Scheduler processes: