Most frequently asked SAS Interview Questions

Jittery before your first interview? Fret not! The easiest way to score and make your mark involves in-depth knowledge and good communication skills. Besides, what‘s vital is to upgrade yourself and be aware of the changes happening around in your field of expertise.

Here are some of the most frequently asked SAS interview questions and answers. Whenever answering, be short, to the point and avoid rambling.

How can you define SAS?

SAS, or Statistical Analytics System, is a software suite developed by the SAS Institute. Essentially, SAS is used in business intelligence and advanced data management and data analytics. Also, SAS provides a user interface for lay users through the quintessential SAS language system.

Generally speaking, the output statement is used to save a summarized view of data statistics. Apart from that, it acts as an important alternative to the CAPABILITY procedure in order for the calculation and saving of percentiles. Additionally, the OUTPUT statement can also be used in order to specify the title or name of the output data set.

Can you highlight the differences between PROC MEANS and PROC SUMMARY?

So far as PROC MEANS is concerned, it is used to trot out subgroup statistics upon the application of a BY statement. Also, it cannot be used unless and until the BY variables have once been used to sort elements of the input data.

PROC SUMMARY, on the other hand, is a more useful tool in that it furnishes info/stats for all the subgroups at once, instead of employing the PROC MEANS individually each time.

Can you highlight the chief differences between do while and do until statements?

Importantly, the do while loop is an entry controlled loop. Also, it checks whether the statement is true or false before execution. If it is false, it doesn’t go ahead. Do until, on the other hand, executes at least once, irrespective of the condition.

Also known as the column pointer, the trailing @ is chiefly used to peruse a line of your unchecked data before reading additional data in the same record. The double trailing, on the other hand, releases the present data line only upon its exhaustion. In other words, the data line must be read completely before being double trailed.

Can you define interleaving in SAS?

Chiefly, the purpose of interleaving is to conglomerate different sorted data sets into one data set. Interleaving, therefore, may be defined as the method by which data sets are injected a measured degree of homogeneity; in short, it can be said that interleaving is a kind of data bundling or data combination.

Can you highlight the entire procedural work of PROC SQL in SAS?

First of all, SAS checks for syntax errors in each and every statement. Secondly, the SQL optimizer decides upon the execution of the SQL query. Thirdly, the tables evolved out of the FROM statement are included in the data. Then, all the relevant codes and calculations are executed consecutively and the final table is created. Lastly, this table is relayed to the output table.

Can you explain the purpose of the APPEND statement? Also, what do you mean by RUN-GROUP processing?

Basically defined, the APPEND is typically meant to combine one SAS data set with another SAS data set. RUN-GROUP, on the other hand, is chiefly used for the submission of a PROC step by using the RUN statement. However, the key point to keep in mind is that the procedure should not be terminated.

Can you explain briefly the meaning of PDV? Also, what exactly do you mean by a data step?

PDV, or Program Data Vector, is the region of memory where the respective data sets are created through the SAS, one at a time. Data values are assigned to their respective data variables by the input buffer upon the execution of the concerned program.

A data step, on the other hand, is chiefly used for the purpose of creating SAS data sets by the manipulation of the data.

Explain the BOR function. Also, what are CALL PRXCHANGE and CALL PRXFREE Routine?

So far as the BOR function is concerned, it is a bitwise logical relation which is chiefly used for the purpose of returning logical OR between two corresponding statements.

CALL PRXFREE Routine, on the other hand, is chiefly used for the purpose of allocation of free memory. The CALL PRXFREE Routine is basically used for character string matching. CALL PRXCHANGE, as the name suggests, is basically used for the purpose of pattern matching replacement.