ALTER FRAGMENT

>>-ALTER FRAGMENT ON-------------------------------------------->
 
                                                 (1)
>--+-TABLE--surviving_table--+-| ATTACH Clause |---------------+-+-><
   |                         |                   (2)           | |
   |                         +-| DETACH Clause |---------------+ |
   |                         |                 (3)             | |
   |                         +-| INIT Clause |-----------------+ |
   |                         |                (4)              | |
   |                         +-| ADD Clause |------------------+ |
   |                         |  (5)                   (6)      | |
   |                         '------+-| DROP Clause |--------+-' |
   |                                |                   (7)  |   |
   |                                '-| MODIFY Clause |------'   |
   |  (5)                                             (3)        |
   '--------INDEX--surviving_index--+-| INIT Clause |--------+---'
                                    |                (4)     |
                                    +-| ADD Clause |---------+
                                    |                 (6)    |
                                    +-| DROP Clause |--------+
                                    |                   (7)  |
                                    '-| MODIFY Clause |------'

Notes:

Element	Description	Restrictions	Syntax
surviving _index	Index on which to modify the distribution or storage	Must exist when the statement executes	Database Object Name
surviving _table	Table on which to modify the distribution or storage	Must exist. See Restrictions on the ALTER FRAGMENT Statement.	Database Object Name

The ALTER FRAGMENT statement applies only to table fragments or index fragments that are located at the current site (or the current cluster, for Extended Parallel Server). No remote information is accessed or updated.

You must have the Alter or the DBA privilege to change the fragmentation strategy of a table. You must have the Index or the DBA privilege to alter the fragmentation strategy of an index.

Attention:

This statement can cause indexes to be dropped and rebuilt. Before undertaking alter operations, check corresponding sections in your IBM Informix Performance Guide to review effects and strategies.

Clauses of the ALTER FRAGMENT statement support the following tasks.

Clause

Effect

ATTACH

Combines two or more tables that have the same schema into a single fragmented table

DETACH

Detaches a table fragment (or in Extended Parallel Server, a slice) from a fragmentation strategy, and places it in a new table

INIT

Provides the following options:

Defines and initializes a fragmentation strategy on a table
Creates a fragmentation strategy for tables
Changes the order of evaluation of fragment expressions
Alters the fragmentation strategy of a table or index
Changes the storage location of an existing table

ADD

Adds an additional fragment to an existing fragmentation list

DROP

Drops an existing fragment from a fragmentation list

MODIFY

Changes an existing fragmentation expression

Use the CREATE TABLE statement or the INIT clause of the ALTER FRAGMENT statement to create fragmented tables.

After a dbspace has been renamed successfully by the onspaces utility, only the new name can reference the renamed dbspace. Existing fragmentation strategies for tables or indexes are automatically updated, however, by the database server to replace the old dbspace name with the new name. You do not need to take any additional action to update a distribution strategy or storage location that was defined using the old dbspace name, but you must use the new name if you reference the dbspace in an ALTER FRAGMENT or ALTER TABLE statement.

ALTER FRAGMENT

Syntax

Usage