The default
macro variable values automate processing decisions. The default settings provide good performance.
However, optimal performance requires changes to the default settings of some macro
variables. Before you make changes to the default settings, consider conducting performance
testing first. After you quantify performance parameters by using several macro variable
settings, you can customize
SPD Server so that it solves your business or data problems with maximum efficiency.
Each SPD Server installation is different. You might want to change many values, or
just a few. Either
way, macro variables are flexible and easy to manipulate.
You can place the macro variable assignment anywhere in the open code of a SAS program
except in the data lines. The
most convenient location for your %LET statements to initialize macro variables is
in your autoexec.sas file or at the beginning of a program. The macro variable assignment
is valid for the duration of your
session or the executing program. Macro variable values remain in effect until they are changed
by a subsequent assignment.