When using 7.x or a later file format, you can use the following data types when you define a key:

If you are using the 6.x file format, you can use all the preceding types to define a key except for CURRENCY and TIMESTAMP.

If you are using a file format prior to 6.x, NUMERICSA and NUMERICSTS are not available as data or key types.

For more information on data types, see the following topic in SQL Engine Reference: Data Types.