NULL and Blank in different INFORMIX Version

[ttkong]

Hi all,

Is anybody know that NULL and bank ("&quot is considered same value when assigning to a variable in INFORMIX version 5 or older? For example:

LET a = NULL

is equal to

LET a = ""

or

LET a = NULL
LET b = ""

IF a = b THEN # True
....
END IF

From my understanding, INFORMIX 4GL version 7 treats the above differently. That is, NULL <> &quot;&quot;. If the above statement is correct, is there any INFORMIX utility that could make INFORMIX version 7.x accept the 4GL codes previously coded in version 5, without any changes to the code?

Thanks.

Rgrds,
TTKong

 

[olded]

Hi:

According to everything, i've read about null, the result of this code:

LET a = NULL
LET b = &quot;&quot;

IF a = b THEN # True
....
END IF

is unspecified. For checking for null for equality of inequality. You have to do this:

IF a = b or a IS NULL or b IS NULL THEN
.

Regards,

Ed