SAS Certified Professional Prep Guide

Using the UNION Set Operator

A Brief Overview

The set operator UNION does both of the following:

• selects unique rows from both tables
• overlays columns

Figure 4.5 UNION Set Operator Relationship

Example: Using the UNION Operator Alone

To display all rows from the tables Col1 and Col2 that are unique in the combined set of rows from both tables, use a PROC SQL set operation that includes the UNION operator.

proc sql;
   select *
      from certadv.col1 union
   select *
      from certadv.col2;
quit;

Output 4.16 PROC SQL Query Result Illustration

With the UNION operator, PROC SQL first concatenates and sorts the rows from the two ...