The ACTIVATE DATABASE command starts up selected databases. Using this command in a partitioned database results in an attempt to activate the selected partitioned database on all database partitions. By using this command, no application time is spent on database initialization or startup.
Databases that you have initialized using the ACTIVATE DATABASE command must be shut down with the DEACTIVATE DATABASE command or with the db2stop command; the last application disconnecting from the database will not shut it down. For more information on the ACTIVATE and DEACTIVATE commands, refer to the Command Reference manual.
If a database has not been started, and a CONNECT TO (or an implicit connect) is encountered in an application, then the application must wait while the database manager starts up the required database before it can do any work with that database. This is a startup cost that is borne by the first application to access a particular database. In a partitioned database, this startup cost is incurred on each database partition. Once the database is started, all other applications can connect to and use the database without a time cost associated with the database startup.