Cannot disable index during PL/SQL procedure

I've written a PL/SQL procedure that would benefit if indexes were first disabled, then rebuilt upon completion. An existing thread suggests this approach:

alter session set skip_unusable_indexes = true;

alter index your_index unusable;

[do import]

alter index your_index rebuild;

However, I get the following error on the first alter index statement:

SQL Error: ORA-14048: a partition maintenance operation may开发者_如何学JAVA not be combined with other operations
ORA-06512: [...]
14048. 00000 -  "a partition maintenance operation may not be combined with other operations"
*Cause:    ALTER TABLE or ALTER INDEX statement attempted to combine
           a partition maintenance operation (e.g. MOVE PARTITION) with some
           other operation (e.g. ADD PARTITION or PCTFREE which is illegal
*Action:   Ensure that a partition maintenance operation is the sole
           operation specified in ALTER TABLE or ALTER INDEX statement;
           operations other than those dealing with partitions,
           default attributes of partitioned tables/indices or
           specifying that a table be renamed (ALTER TABLE RENAME) may be
           combined at will

The problem index is defined so:

CREATE INDEX A11_IX1 ON STREETS ("SHAPE")
  INDEXTYPE IS "SDE"."ST_SPATIAL_INDEX" PARAMETERS
  ('ST_GRIDS=890,8010,72090 ST_SRID=2');

This is a custom index type from a 3rd-party vendor, and it causes chronic performance degradation during high-volume update/insert/delete operations.

Any suggestions on how to work around this error? By the way, this error only occurs within a PL/SQL block.

Edit: Here is the procedure in its entirety:

procedure disable_indexes (
  tbl_name in varchar2
) as
  stmt varchar2(200);
  cursor curs(v_tbl_name in varchar2) is
    select 'alter index ' || index_name || ' unusable;' as ddl_stmt
    from user_indexes
    where upper(table_owner) = upper(user)
    and upper(table_name) = upper(v_tbl_name)
    and ityp_name in ('CTXCAT', 'ST_SPATIAL_INDEX');
begin
  for r_curs in curs(tbl_name) loop
    dbms_output.put_line(r_curs.ddl_stmt);
    execute immediate r_curs.ddl_stmt;
  end loop;
end;

If this is really your code and not a pseudo-code rewrite, remove the ; at the end of your statement in the stmt variable (otherwise you will run into ORA-00911: invalid character during execution)

Now if your process works manually, you should be able to make it work with execute immediate in a procedure. Make sure that this is not a role issue (see this article by Tom Kyte) by issuing SET ROLE NONE before executing the commands manually.

Have you tried to do a DROP INDEX before and then recreate it after?