This CREATE INDEX statement cannot be executed because an index on the same column or combination of columns already exists. For a given collation order, at most two indexes can exist on any combination of columns, one ascending and one descending.
To display the indexes on a particular table, join sysindices and systables. Supply table-name in the following statement:
SELECT * FROM sysindices, systables WHERE sysindices.tabid = systables.tabid AND systables.tabname = 'table-name'