Disables, but does not delete, the specified index.

    When managing a very large database, an index can become corrupt
    or unsuitable for query optimization. If the table on which the
    index has been defined is very large, it may take a considerable
    amount of time to execute the DROP INDEX statement. Using the
    MAINTENANCE IS DISABLED clause of the ALTER INDEX statement
    disables the index so that it is no longer used by the optimizer
    nor is it maintained. You can then execute the DROP INDEX
    statement at a later time even when the table is in use.

    Once an index has been disabled, it may be enabled again using
    the REBUILD PARTITION clause.

    To disable an index, you must have DROP privileges to the table
    on which the index is defined, and there can be no active queries
    on the table.