SAS包含所有代码

Question

There's a big data download to do using SAS (Proc SQL).

Sometimes I require to look at a particular customer number, or a couple customer numbers and equally often will require every customer number.

I would like to set up a macro variable so that the user can enter in either the customer numbers they require, or can enter some short version which will include everything.

ie %Let dCustomer_Number = in (3123, 1234) where &dCustomer_Number would be in the WHERE section of the query.

A colleague informed me that in SQL you can use an * (asterisk) to include every customer number.

The closest I have come across is like '%' but this does not seem to work for numeric variables. Is there something similar which will work?

I know it could be easy enough to just delete the where statement for the customer number filter but I don't want the user to have to actually alter the code, only the macro variables at the start.

Thanks

Answer 1

Generate different where clause based on whether the list of customer numbers is empty or not. Normally you can use an obviously true expression, such as 1=1 , to add to your WHERE clause so that your full statement syntax doesn't change.

If you are not using a macro you can use IFC() function to generate your where clause conditionally

%*let dCustomer_Number = 3123,1234 ;
%let dCustomer_Number = ;
%let where_clause = %sysfunc(ifc
   (%length(&dCustomer_Number)
  ,(Customer_Number in (&dCustomer_Number))
  ,(1=1)
));
...
where &where_clause;