how to use where statement?

[Raj00007]

i am a basic SAS learner. how to use where statement, when the variable it self as a where.

data task1;
set sasuser.Acities;
run;

data task2;
set task1;
where 'Country where Aiport is located' = 'USA';
run;

[Kurt_Bremser]

A variable is a variable is a variable, not "a where".

The most simple WHERE condition is usually a comparison of a variable with a literal value, like

where country = 'USA';

Your code also does not need the first data step, you can reference sasuser.acities directly in the second step.

[PaigeMiller]

As written, your comparison of 

where 'Country where Aiport is located' = 'USA';

will always fail because the text string 'Country where Aiport is located' is never equal to the text string 'USA'

I think what you might want is a variable name instead of the text string 'Country where Aiport is located', but only you know what that variable name would be. I use "variablename" as the variable name, of course you would use the actual variable name.

Like this:

data task1;
set sasuser.Acities;
where variablename = 'USA';
run;