topic Re: Parenthesis or No Parenthesis in SAS Procedures

Parenthesis or No Parenthesis

omega1983 — Tue, 02 Apr 2013 17:42:24 GMT

proc sql;

create table Members as

select ID, L_Name, Join_Date, Member_Type, Area, Member_Code,Partner_Code, Supvr_Code, Refund_Amt, Balance_Owed

from tbl_Membership

where Member_Type in ('Loss','Active','Contingent') and Member_Code ne '3' or

Member_Code eq '3' and Area = '24' or

Partner_Code eq '1' and Supvr_Code = '5' and

Balance_Owed >0;

quit;

In my output, I am getting some records with a zero. I am trying to determine when and where to enclose my or groups and "and' gropus in parenthesis. I do not deal with this many scenarios often so I want to get a good feel for general rules when dealing with an assortment of and vs or groups.

Re: Parenthesis or No Parenthesis

Reeza — Tue, 02 Apr 2013 18:07:10 GMT

Parenthesis are used for specifying the order of how AND/OR are evaluated. Otherwise I think they're evaluated from left to right, which isn't necessarily what you want.

I'll add in the business logic in comments as well so it makes sense to me in the future and for updates.

WHERE

((Member_Type in ('Loss','Active','Contingent') and Member_Code ne '3') /*Member is active (ne 3) and delinquent*/

or (Member_Code eq '3' and Area = '24') /* OR Member is active and in Los Angeles*/

or (Partner_Code eq '1' and Supvr_Code = '5') ) /* OR Accounts where the partner is senior and supervisor is not*/

and Balance_Owed >0 /*Any of the above AND Accounts that have a balance outstanding*/

;

Re: Parenthesis or No Parenthesis

Ron_MacroMaven — Wed, 03 Apr 2013 14:28:35 GMT

Here are some references on

Evaluating Logical Expressions

http://www.sascommunity.org/wiki/Evaluating_Logical_Expressions

This is the support.sas page on order of precedence of evaluation of logical operators

Defining Arithmetic and Logical Expressions

SAS(R) 9.3 Macro Language: Reference

Ron Fehd logically yours