 Activating or Deactivating Indexes
Activating or Deactivating Indexes 
If you deactivate an index, the database system no longer uses it to access data in the database.
You are logged on to the database as a database user.
You have the INDEX privilege for the table for which the index has been defined.
More information: SQL Reference Manual, Privilege Specification (privilege_specification)
The database is in the ONLINE operational state.
Open the index overview.
More information: Displaying Indexes
To activate an index, choose Enable in the context menu of the index.
To deactivate an index, choose Disable in the context menu of the index.