Oracle^® Business Intelligence Data Warehouse Administration Console Guide > Common Tasks Performed in the DAC >

Determining the Number of Transactional and Data Warehouse Database Connections

This section describes how to determine the maximum number of database connections you need between the DAC server and the transactional database and the DAC server and the data warehouse database. You set the Max Num Connections parameter when you create the transactional and data warehouse database connections.

For the transactional database, the DAC server uses these connections to perform change capture. The number of connections you set for this connection pool determines how many change capture processes can run concurrently. If you have a powerful transactional database server and are going to run ETL processes during off-peak times, you can increase the Max Num Connections setting to 15 or 20 (10 is the default). If you have a less powerful transactional database server, you should not overload the operational system with ETL processes. Therefore, you should set the value below 10.

For the data warehouse database, the DAC server uses these connections to perform processes such as truncate tables, drop and create indices, and analyze tables. You should not set the Max Num Connections value higher than the Maximum Sessions parameter value (the maximum number of workflows that can be executed in parallel on the Informatica server) because these values have a one to one relationship.