Location of Ingres Files
Before installing Ingres, you must decide on locations for the Ingres files. Choose these locations carefully because they cannot be easily changed once specified. The exception to this rule is the location of the transaction log.
During installation, you will provide the directory path for each instance default location, and it will be recorded in an Ingres environment variable/logical (for example, the location for the system files is stored in II_SYSTEM).
After installation, you can create additional locations of all types except II_SYSTEM. Every user database must have at least one Database, Work, Checkpoint, Dump, and Journal location, but these locations can be anywhere and no database—except the master (iidbdb)—is required to use the instance default locations. If you have enough disks to create additional locations, the choice of locations for each database should follow the same guidelines as for the instance defaults.
For development or test machines where you periodically refresh a copy of the production database, we recommend that the two copies of the database be "checkpoint compatible" (same Data, Work, Checkpoint, Dump, and Journal location names and paths). Checkpoint compatibility allows simple restoration of a production checkpoint to the test instance.