Logical Operators And OR - operating mode

[chriys1337]

Hi,

I am working on an if condition and questioning how it is working:

if(x=1 and y=0 or y= null(),'yes','no') as test

is it (1st condition must be valid AND 2nd  condition must be valid) OR 3rd condition must be valid (only)

vs

1st condition must be valid AND (2nd condition must be valid OR 3rd condition must be valid) ?

If it is working like described in the second mode, I would need to rewrite my if statement to

if(x=1 and y=0 or x=1 and y= null(),'yes','no') as test2

Thanks for sharing your insights.

[Vegar]

When more than one logical operator is used in a condition, NOT is evaluated first, then AND, and finally OR. The best way to straighten this so there no confusion is to group the logical bulks with parentheses. 

if(x=1 and (y=0 or y= null() ),'yes','no') as test

In your case I would also recommend to switch the y=null() with isnull(y) like this 

if(x=1 and( y=0 or isnull(y)) ,'yes','no') as test