ALTER INDEX statement

Description

Renames indexes in base or global temporary tables and foreign key role names of indexes and foreign keys explicitly created by a user.

Syntax

ALTER { INDEX index-name
| [ INDEX ] FOREIGN KEY role-name
| [ INDEX ] PRIMARY KEY
| ON [owner.]table-name   { rename-clause | move-clause }

Parameters

rename-clause: : RENAME TO | AS new-name

move-clause:: MOVE TO dbspace-name

Examples

Example 1

The following statement moves the primary key, HG for c5, from dbspace Dsp4 to Dsp8.

CREATE TABLE foo 
	c1 INT IN Dsp1,
	c2 VARCHAR(20),
	c3 CLOB IN Dsp2,
	c4 DATE,
	c5 BIGINT,
	PRIMARY KEY (c5) IN Dsp4) IN Dsp3;

CREATE DATE INDEX c4_date ON foo(c4) IN Dsp5;

ALTER INDEX PRIMARY KEY ON foo MOVE TO Dsp8;

Example 2

Moves DATE index from Dsp5 to Dsp9

ALTER INDEX c4_date ON foo MOVE TO Dsp9

Example 3

Renames an index COL1_HG_OLD in the table jal.mytable to COL1_HG_NEW:

ALTER INDEX COL1_HG_OLD ON jal.mytable 
RENAME AS COL1_HG_NEW

Example 4

Renames a foreign key role name ky_dept_id in table dba.Employees to emp_dept_id:

ALTER INDEX FOREIGN KEY ky_dept_id
ON dba.Employees 
RENAME TO emp_dept_id

Usage

The ALTER INDEX statement renames indexes and foreign key role names of indexes and foreign keys that were explicitly created by a user. Only indexes on base tables or global temporary tables can be renamed. You cannot rename indexes created to enforce key constraints.

ON clause The ON clause specifies the name of the table that contains the index or foreign key to rename.

RENAME [ AS | TO ] clause The RENAME clause specifies the new name of the index or foreign key role.

MOVE clause The MOVE clause moves the specified index, unique constraint, foreign key, or primary key to the specified dbspace. For unique constraint or foreign key, you must specify its unique index name.

You must have DBA authority or have CREATE privilege on the new dbspace and be the table owner

Attempts to alter an index in a local temporary table return the error “index not found.” Attempts to alter a nonuser-created index, such as a default index (FP), return the error “Cannot alter index. Only indexes in base tables or global temporary tables with an owner type of USER can be altered.”