The following example describes a combined method of paging a subfile that
uses system resources efficiently. In some applications, the number of
records in the subfile could be quite large. However, the application
user may want to view only the first page or two of these records. In
this case, it may be faster and more efficient for the application program to
build the subfile a page at a time as requested by the user. The OS/400
program handles the paging of records in the subfile. It also returns a
Page Up key indicator to the high-level language program when another page
should be added to the end of the subfile. The application user can
detect no difference between a page up request handled by the OS/400 program
and one handled by the high-level language program.
+--------------------------------------------------------------------------------+
| |
|NAME DEPARTMENT PHONE |
| |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
|XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX XXXXXXXXXX NNNN |
| |
| |
+--------------------------------------------------------------------------------+
The following keywords are important in the example:
SFLPAG
SFLSIZ
The SFLSIZ value is larger than the SFLPAG value. The subfile is paged by the SFLPAG value.
Figure 9. Subfile with Paging by OS/400 Program and High-Level Language Program in DDS
|...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+....8
00010A R SETSFL SFL
00020A 50 SFLNXTCHG
00030A NAME 30 0 5 2
00040A DEPT 10 5 40
00050A PHONE 4 0 5 58
00060A R SETCTL SFLCTL(SETSFL)
00070A SFLSIZ(0034) (1)
00080A SFLPAG(0017)
00090A 40 SFLDSP
00100A 41 SFLDSPCTL
00110A 42 SFLDLT
00120A 43 SFLCLR
00130A 49 SFLEND (2)
00140A N49 ROLLUP(26)
00150A LOCK
00160A OVERLAY
00170A SETRRN 4S 0H SFLRCDNBR(CURSOR)(3)
00180A 3 2'NAME'
00190A 3 40'DEPARTMENT'
00200A 3 58'PHONE'
A
Legend:
Records in the subfile with changed input fields (modified data tags) will be changed after a new page is added to the subfile by the high-level language program.
(C) Copyright IBM Corporation 1992, 2005. All Rights Reserved.