Four ways to create add macro to Global Macro Table

　　　　• Create the macro variable in open code.

　　　　• List the macro variable on a %GLOBAL(default value is null) statement in the macro program in which it is defined.

　　　　• Create the macro variable in a DATA step with CALL SYMPUTX when the global symbol table is specified.

　　　　• Define a global macro variable with the INTO clause on the PROC SQL SELECT statement.