Storing virtual data in an extspace
An extspace lies outside the disk storage that is configured for the database server. To create a physical extspace, you might use an operating system command or use a data management software system.
An extspace can have a location other than a path or file
name because the database server does not interpret the location.
Only the access method uses the location information.
Important: The use of external storage for secondary access
methods is discouraged because you must provide transaction integrity,
rollback, and recovery for indexes that are in external storage spaces.
If the access method requires external-space support, follow the guidelines
in this section.
To store virtual data in an extspace, take one of the following actions:
- Create logical names for existing external storage with the onspaces utility. Then, specify the reserved name or names when you create a virtual index with the CREATE INDEX statement.
- Directly specify an existing physical external storage location as a quoted string in the CREATE INDEX statement.
- Provide a default physical external storage location, such as a disk file, in the access-method code.