File Types and Processing Methods
Table 1 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:
- Relative-record-number processing
- Consecutive processing
- Sequential-by-key processing
- Random-by-key processing
- Sequential-within-limits processing.
Access | Method | Opcode | Position 28 | Position 34 | Position 35 | Explanation |
---|---|---|---|---|---|---|
Random | RRN | CHAIN | Blank | Blank | Blank | Access by physical order of records |
Free-form syntax: (No keyword is necessary) | ||||||
Sequential | Key | READ READE READP READPE cycle | Blank | Blank | I | Access by key sequentially |
Free-form syntax: KEYED keyword | ||||||
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 |
Free-form syntax: (Not supported for a free-form file definition) | ||||||
Sequential | RRN | READ cycle | Blank | Blank | T | Access sequentially restricted to RRN numbers in record-address file |
Free-form syntax: (Not supported for a free-form file definition) |
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 Rational Development Studio for i: ILE RPG Programmer's Guide.