DROP CLUSTER DESCRIPTION (Adabas Only)
Function
This statement deletes the logical representation of a cluster while preserving underlying Adabas file.
Note:
Dropping a cluster description does not cause all data contained within to be deleted. Only the cluster description in the catalog is deleted.
Syntax
DROP CLUSTER DESCRIPTION cluster_specification [ | CASCADE | RESTRICT]
where
cluster_specification | Schema identifier and table identifier of the master table in the cluster description to be dropped. The default schema name is assumed if not specified here. See
Cluster Specification. |
Description
A cluster definition and all its associated information will be deleted from Adabas SQL Gateway Embedded SQL's catalog. Any other statements referencing this cluster will no longer be valid. In addition, any attempts to compile statements which reference this cluster will fail. Even if the cluster description is re-specified, all previously compiled statements remain invalid.
If the CASCADE option is specified, all dependent view descriptions based on the cluster to be dropped, will be deleted as well.
If the RESTRICT option is specified, the statement execution will be rejected if there are dependent views.
If neither of these two option is specified, RESTRICT is assumed.
If the statement is invoked statically, then during pre-compilation, the schema does not need to exist in the catalog. For successful execution, however, the schema must exist in the catalog, regardless of how it is invoked.
Limitations
The DBA can execute this statement for all users. All other users can use this statement only in a schema owned by the user.
The specified table specification must denote an existing cluster at runtime.
Warning:
This statement is not subject to transaction logic. An implicit COMMIT will be performed after successful execution of this statement. If an error is detected during execution of this statement, an implicit ROLLBACK will be performed. Therefore, before executing this statement, it is strongly recommended to complete any open transaction containing INSERT, UPDATE and/or DELETE statements by issuing an explicit COMMIT or ROLLBACK statement.
ANSI Specifics
The DROP TABLE DESCRIPTION statement is not part of the Standard.
Examples
The following example deletes all cluster descriptions of the cluster city_guide and all related views:
DROP CLUSTER DESCRIPTION city_guide CASCADE;