An explicit journaling option on the ckpdb command causes the checkpoint to be taken offline (that is, when no one is using the database) and with an exclusive lock on the database.

The first time journaling is turned on in a particular database, you must checkpoint the database with journaling enabled (ckpdb +j dbname). Doing so ensures that the checkpoint is taken offline.

Once you have enabled journaling by checkpointing offline with the +j option, you can maintain the “journaling on” status and take checkpoints online (that is, when users are using the database) by not subsequently setting the +j option on ckpdb. Online checkpoints permit users to continue using the database while the checkpoint is being taken.

After you have enabled journaling for the database by checkpointing offline with the +j option, you can take an offline checkpoint to start journaling of tables for which journaling is enabled after the next checkpoint.