The following table describes the optional

UOW Count

connection attribute:

A unit of work (UOW) is a collection of changes within a single commit scope that a transaction makes on the source system. Each UOW can contain a different number of changes.

PWXPC reads change data from PowerExchange and provides the data to the source qualifier, at which point the count of UOWs begins. When you use a non-zero value for the

UOW Count

attribute, PWXPC issues a real-time flush to commit the change data to the target after the UOW count reaches the specified value. When PWXPC issues a real-time flush, it writes the following message to the session log:

For example, if the

UOW Count

value is 10, the PowerCenter Integration Service commits all change data read from the source to the target after the tenth UOW is processed.

The lower you set the

UOW Count

value, the faster the PowerCenter Integration Service commits data to the target. If you require the lowest possible latency for applying change change data to targets, specify a

UOW Count

value of 1.

Commit processing is not controlled solely by the

UOW Count

attribute. The

Maximum Rows Per commit

, and

Real-Time Flush Latency

attributes also determine the commit frequency.

If you have many small UOWs, you can use the

UOW Count

or

Minimum Rows Per commit

attribute or both to create a consistent flow of UOWs that can be committed to the target in batches of approximately the same size.

You can also control commits that occur at UOW boundaries based on time by specifying the

Real-time Flush Latency

attribute. Specify the

UOW Count

or

Real-time Flush Latency

attribute or both. If you specify both, a commit occurs when either limit is reached.