Table 50 shows the valid entries for positions 28, 34, and 35 of the file description specifications for the various file types and processing methods. The methods of disk file processing include:
| Access | Method | Opcode | Position 28 | Position 34 | Position 35 | Explanation |
|---|---|---|---|---|---|---|
| Random | RRN | CHAIN | Blank | Blank | Blank | Access by physical order of records |
| Sequential | Key | READ READE READP READPE cycle | Blank | Blank | I | Access by key sequentially |
| Sequential | Within Limits | READ READE READP READPE cycle | L | A, P, G, D, T, Z, or F | I | Access by key sequentially controlled by record- address-limits file |
| Sequential | RRN | READ cycle | Blank | Blank | T | Access sequentially restricted to RRN numbers in record-address file |
For further information on the various file processing methods, see the section entitled "Methods for Processing Disk Files", in the chapter "Accessing Database Files" in the IBM Rational Development Studio for i: ILE RPG Programmer's Guide.