Join fields

 

Here are the rules for join fields.

• Every physical file you join must be joined to another physical file by at least one join field. A join field is a field specified as a parameter value on the JFLD keyword in a join specification.

• Join fields (specified on the JFLD keyword) must have identical attributes (length, data type, and decimal positions) or be redefined in the record format of the join logical file to have the same attributes. If the join fields are of character type, the field lengths might be different.

• Join fields need not be specified in the record format of the join logical file (unless redefine one or both so that their attributes are identical).

• If you redefine a join field, you can specify N in position 38 (making it a neither field) to prevent a program using the join logical file from using the redefined field.

• The maximum length of fields used in joining physical files is equal to the maximum size of keys for physical and logical files.

 

Parent topic:

Summary of rules

 

Related reference

Database file sizes