A database is either Active or Inactive. If it is Inactive, it is not taking up resources (memory) on the server and no one is accessing the data. A database can become active by one of two ways. Either the ACTIVATE database command is issued, or when the first connection occurs. When a database becomes active, all of the heaps and bufferpools are allocated. This can take some time, which maybe undesirable when connecting to the database for the first time. The ACTIVATE DATABASE command will bring up the database and allocating heaps and buffperpools so that the connections do not experience the delay of bringing up the database if it is the first connection. If a database have been ACTIVATEd, it will remain active even when the last connection ends.
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