ADELIA |
VADELIA |
SADELIA |
WADELIA |
EADELIA |
(I/B) |
(I/B) (C/S) |
(B) (S) |
(I/B) (C/S) |
(B) (C/S) |
Section for use
All
Syntax
IF ViewName EXISTS
Description
This instruction is a logical operator which can only appear in a condition.
It tests whether a file access was successful.
A reading or positioning instruction must have taken place beforehand.
The variable ViewName located before the instruction must be the guide word of a view declared at the prototype level.
Example
* Controls the ITEM file
*
PREPARE_MSG 0057 Z_ITEM_CODE
CHAIN ITEM_VW
IF ITEM_VW EXISTS AND MODE = 'CREATE'
* already exists
INIT_MSG Z_ITEM_CODE MODE
ANOMALY
END
*
IF ITEM_VW DOES_NOT_EXIST AND MODE = 'UPDATE'
* record does not exist
INIT_MSG Z_ITEM_CODE MODE
ANOMALY
END
*
*
CHAIN ITEM_SIZES
DO_WHILE ITEM_SIZES EXISTS
NEW_COLOR = 'Blue'
UPDATE ITEM_SIZES
READ_EQUAL ITEM_SIZES
REDO