The ODBC driver extends the SQL grammar with alternate CREATE INDEX and DROP INDEX statements, allowing an index created using the alternate CREATE INDEX syntax to be dropped using the alternate DROP INDEX syntax, by just specifying the index name and not also the associated table name and either the column list or index name.
This feature was originally designed for earlier versions of ODBC, and will be deprecated in a future release. The alternate syntax for both CREATE INDEX and DROP INDEX is not standard and not portable. The recommendation is to use the Teradata SQL database syntax for these statements as described in SQL Data Definition Language (B035-1144).