SAS processing
is the way that the SAS language reads and transforms input data and
generates the type of output that you request. The DATA step and the
procedure (PROC) step are the two steps in the SAS language. Generally,
the DATA step manipulates data, and the PROC step analyzes data, produces
output, or manages SAS files. These two types of steps, used alone
or combined, form the basis of SAS programs.
The following figure
shows a high–level view of SAS processing using a DATA step
and a PROC step. The figure focuses primarily on the DATA step.
You can use different
types of data as input to a DATA step. The DATA step includes SAS
statements that you write, which contain instructions for processing
the data. As each DATA step in a SAS program is compiling or executing,
SAS generates a log that contains processing messages and error messages.
These messages can help you debug a SAS program.