DATE function
Syntax:
DATE ( expression [ , format-code ] )
Official description:
The DATE function formats the expression as a date according to the string given as format-code. If the format-code is omitted, the date format set in the operating system is used.
Parameters:
expression
can be numeric or alphanumeric.
Typically alphanumeric representing a date.
If numeric it also represents a date but as an offset from day 0 (zero) in QVW's date arithmetic
Numeric value for expression
|
Date that they numeric value represents in YYYY-MM-DD format
|
|
1899-12-30
|
||
1899-12-31
|
||
4637-11-26
|
||
1899-12-29
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Outstanding questions:
Q. If the format-code is omitted, the date format set in the operating system is used.Do other SET system variables impact this?
Error situations:
DATE function returns NULL if it cant resolve the format to
the ‘number’ supplied
Example : The format of the date supplied (1st parameter) does not match the format-code (2nd parameter)
LET x=DATE ('01-01-2015', 'YYYY-MM-DD') ;
IF ISNULL (x) THEN ;
let x='NULL' ;
end if ;
TRACE x=[$(x)] ;
Gives
x=[NULL]
But it will happily
accept unusual dates i.e. expression (1st parameter) with a value of zero:
LET x=DATE (0, 'YYYY-MM-DD') ;
IF ISNULL (x) THEN ;
let x='NULL' ;
end if ;
TRACE x=[$(x)] ;
IF ISNULL (x) THEN ;
let x='NULL' ;
end if ;
TRACE x=[$(x)] ;
Gives
x=[1899-12-30]
