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DROP DBEFILE

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The DROP DBEFILE statement removes the row describing a DBEFile from the SYSTEM.DBEFile.

Scope

ISQL or Application Programs

SQL Syntax

  DROP DBEFILE DBEFileName

Parameters

DBEFileName

is the name of the DBEFile to be dropped.

Description

  • Before dropping a DBEFile previously associated with a DBEFileSet via an ADD DBEFILE statement, you must use the DROP INDEX and DROP TABLE statements to empty the DBEFile, then use the REMOVE DBEFILE statement to remove the DBEFile from the DBEFileSet.

  • Although information for the dropped DBEFile is removed from the SYSTEM.DBEFile, the file is not removed until the transaction is committed.

Authorization

You must have DBA authority to use this statement.

Example

   CREATE DBEFILE ThisDBEFile WITH PAGES = 4,
                  NAME = 'ThisFile', TYPE = TABLE
 
   CREATE DBEFILESET Miscellaneous
 
   ADD DBEFILE ThisDBEFile TO DBEFILESET Miscellaneous

The DBEFile is used to store rows of a new table. When the table needs an index, one is created.

   CREATE DBEFILE ThatDBEFile WITH PAGES = 4,
                  NAME = 'ThatFile', TYPE = INDEX
 
   ADD DBEFILE ThatDBEFile to DBEFILESET Miscellaneous

When the index is subsequently dropped, its file space can be assigned to another DBEFileSet.

   REMOVE DBEFILE ThatDBEFile FROM DBEFILESET Miscellaneous
 
   ADD DBEFILE ThatDBEFile TO DBEFILESET SYSTEM
 
   ALTER DBEFILE ThisDBEFile SET TYPE = MIXED

Now you can use this DBEFile to store an index later if you need one. All rows are later deleted from the table, so you can reclaim file space.

   REMOVE DBEFILE ThisDBEFile FROM DBEFILESET Miscellaneous
 
   DROP DBEFILE ThisDBEFile

The DBEFileSet definition can now be dropped.

   DROP DBEFILESET Miscellaneous
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