Source file attributes

Here are the attributes common to most source files and the restrictions on using these attributes.

Source files usually have the following attributes:
  • A record length of 92 characters (this includes a 6-byte sequence number, a 6-byte date, and 80 bytes of source).
  • Keys (sequence numbers) that are unique even though the access path does not specify unique keys. You are not required to specify a key for a source file. Default source files are created without keys (arrival sequence access path). A source file created with an arrival sequence access path requires less storage space and reduces save/restore time in comparison to a source file for which a keyed sequence access path is specified.
  • More than one member.
  • Member names that are the same as the names of the objects that are created using them.
  • The same record format for all records.
  • Relatively few records in each member compared to most data files.
Some restrictions are:
  • The source sequence number must be used as a key, if a key is specified.
  • The key, if one is specified, must be in ascending sequence.
  • The access path cannot specify unique keys.
  • The ALTSEQ keyword is not allowed in data description specifications (DDS) for source files.
  • The first field must be a 6-digit sequence number field containing zoned decimal data and two decimal digits.
  • The second field must be a 6-digit date field containing zoned decimal data and zero decimal digits.
  • All fields following the second field must be zoned decimal or character.