Language basics / Type conversions |
By default, in case of conversion error, the program flow continues, the target variable is set to NULL and the global STATUS variable is not set.
In order to detect data conversion errors, use the WHENEVER ANY ERROR statement:
MAIN -- DBDATE set to Y4MD- DEFINE v VARCHAR(50), d DATE LET v = "2012-99-99" -- invalid date string LET d = v DISPLAY status, "/", NVL(d,"NULL") -- displays 0/NULL WHENEVER ANY ERROR CONTINUE LET d = v DISPLAY status, "/", NVL(d,"NULL") -- displays -1205/NULL WHENEVER ANY ERROR STOP LET d = "2012-11-23" -- valid date, ok DISPLAY status, "/", NVL(d,"NULL") -- displays 0/2012-11-23 LET d = v -- program execution stopped with error -1205 END MAIN