Ch 15. Indexed File Processing
The Big Picture
- Creation of Master file: A sequential file containing initial
input data must be sorted
- Master File Extension Name in RM/COBOL-85: *.IXF
- Transaction file: Batch data to be used for updating the "Master"
indexed file.
Contains all changes that have occured since "Master" was created
or last updated. It is not required to be sorted by a "key" field.
- On-line interactive updating is possible
Basic Operations
- to create an indexed file - WRITE
- to get a record from an indexed file - READ
- to update a record - REWRITE
- to delete a record - DELETE
- to add a record - WRITE