D=Date Keys

The indexed file (I in position 35) defined on this line is processed by date keys. The D entry must agree with the data format of the field identified as the key field (length in positions 29 to 33 and starting position specified as the parameter to the KEYLOC keyword).

The hierarchy used when determining the format and separator for the date key is:
  1. From the DATFMT keyword specified on the file description specification
  2. From the DATFMT keyword specified in the control specification
  3. *ISO