If the log gets corrupted for any reason, Ingres stops and you have to recover your databases from backup. Therefore, in a live system, it is almost compulsory either to have some type of RAID protection of the log or to have it mirrored by Ingres. In a development environment, mirroring the log is not always necessary. 4.3 Database Locations Files constituting an Ingres database are put in different directories determined by means of Ingres locations. Every location points to the root of a directory tree.
Databases can also share locations.
In Ingres every system table and every user table, and also every index goes in a separate file. By default, backups are created in the checkpoint location of the database. For this reason, the database may change while it is being checkpointed. Ingres places these pages in the dump location. The frequency of this activity is set as a function of the amount of information that is written to the transaction log.