Statistical Analysis System (SAS) Programming Certification Practice Exam

Which program correctly imports only the first seven observations from the external file?

1. options obs=7; proc import data="C:\users\test.txt" out=exam dbms=dlm replace; run; proc print data=exam; run;

2. proc import datafile="c:\users\test.txt" out=exam dbms=dlm replace; options obs=7; run; proc print data=exam; run;

3. proc import datafile="c:\users\test.txt" out=exam dbms=dlm replace; run; proc print data=exam (obs=7); run;

4. proc import datafile="c:\users\test.txt" out=exam dbms=dlm replace; run; proc print data=exam; options obs=7; run;

The correct answer is: options obs=7; proc import data="C:\users\test.txt" out=exam dbms=dlm replace; run; proc print data=exam; run;

The correct program effectively limits the number of observations imported from the external file to the first seven, utilizing the appropriate options statement effectively. By placing the options statement before the PROC IMPORT step, the SAS system is instructed to restrict the input to only the first seven observations right at the beginning of the data import process. This approach is efficient as it prevents unnecessary data from being read into the dataset, thereby optimizing resource usage and performance. The PROC IMPORT procedure itself is set to read the specified external file and parse the data, controlled by the 'dbms=dlm' directive, which indicates that the data is delimited. After the import, the PROC PRINT command is invoked to display the resulting dataset. Since the import was already capped at seven observations, the print procedure will reflect this limitation correctly. The context for the other choices reveals their inefficiency or improper placement of commands. For instance, an options statement placed after the PROC IMPORT would not affect the data being read since it only applies to procedures that follow it. Some choices incorrectly attempt to use options or programmer-defined limits after the data has been imported, which does not fulfill the requirement of importing only the first seven observations initially. This option shows a clear understanding of the order of operations in SAS