With transaction batching, multiple transactions from the log can be returned as a single transaction. Transaction batch sizes are set for a session. If the logged transactions are being fed into another database, transaction batching can improve read performance over the network. For example, a number of inserts could be batched into one transaction so that when the transactions need to be executed in another database, only one transaction needs to be executed.
About this task
The transaction batch setting applies only to the current session and is valid for all reads from SYS_LOG that are started after the setting.
Procedure
Set transaction batch size with the following command:
SET LOGREADER BATCH <size>
The default batch size is 1: no batching of transactions is done.
Results
Setting the batch transaction size does not alter the catchup position; the catchup position can be used to read all transaction in the batch again.