ixPrimary The index is the primary index of the table. (Not applicable to dBASE tables).
ixUnique Each value in the index is unique; there are no duplicates. (Not applicable to all table types.)
ixDescending The index imposes a descending sort order. (Not applicable to all table types.)
ixExpression The index is based on a dBASE key expression. (Only applicable to dBASE tables).
ixCaseInsensitive The index sorts records case insensitively. (Not applicable to all table types.)
ixNonMaintained The index is not automatically updated when the data is edited. (Not applicable to all table types.)
Warning: Attempting to create an index using options that are not applicable to the table type causes AddIndex to raise an exception.
See the vendor-supplied documentation for the particular database system for details on what index options are applicable.