9.11.DROP INDEX Statement

drop_index
        : DROP INDEX NAME opt_table
        ;

opt_table
        : /* empty */
        | q_table_name
        ;

This will drop an index, dba privileges or table ownership are required. A table's primary key which has the same name as the table can not be dropped.

Optionally, a table name can be given if the index name is not unique. The table name may be qualified.