Question-: Data step should always be followed by proc step?
Answer: No, it is not necessary. A Data step can be followed by another Data step or Proc step. Similarly, a proc step can be followed by a Data step. In a program you can have as many Data step and proc step in any order as per the requirement.
Question-: Can we create a new SAS Data set from existing SAS Data set?
Answer: Yes, you can create a new SAS Data set from the existing SAS data set. Which can be done using the various SAS statements like SET, MERGE, MODIFY or UPDATE. You can see below image to understand more.
Question-: Why do you need Data step followed by another Data step sometime?
Answer: We need to sometime format the complex data before doing any analysis using the procedure. In this case we can divided Data step in multiple data step or before analyzing the data we wanted to further process the data.
Question-: In the SAS dataset we know rows are called observation and column name are variables, but what are those in raw file?
Answer: In the raw file we can say each observation is equivalent to the records and each column name is known as field. As you can see in below Raw data first line represent all the fields and 5 records, each data value is separated by “~�