Top 30+ SAS Interview Questions and Answers

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SAS stands for Statistical Analysis System. It was developed at North Carolina State University in the 1960s by Anthony Barr and later expanded by James Goodnight, who co-founded SAS Institute. Originally built for agricultural data analysis, SAS is now widely used in industries like banking, healthcare, and retail for data management and advanced analytics. It plays a key role in roles such as data analyst, SAS programmer, and business intelligence expert. In this blog, we have compiled the most commonly asked SAS interview questions and answers to help you with preparations. 

Fun Fact: Over 65,000 organizations in more than 140 countries use SAS for analytics and data management.

Basic SAS Interview Questions

Here are some basic-level SAS interview questions and answers to help you review the fundamentals.

1. What is the difference between the INPUT and INFILE statements in SAS?

The INFILE statement tells SAS where to find the raw data file – like a CSV or TXT file. The INPUT statement, on the other hand, tells SAS how to read that file. INPUT defines the variables and their formats, while INFILE simply points to the location.

2. What is the role of the Program Data Vector (PDV) in SAS?

The PDV is a temporary memory area where SAS builds each row during the DATA step. It stores variable values, including automatic ones like _N_ and _ERROR_. Once all logic is applied, the complete observation is written from the PDV to the dataset.

3. How does the FORMAT statement differ from the INFORMAT statement?

INFORMAT is used when reading raw data – it tells SAS how to interpret incoming values (like dates or numbers). FORMAT is used when displaying values in output – it controls how values appear, such as showing dates as ddmmyy10. instead of numbers.

4. What does the RETAIN statement do in a DATA step?

RETAIN keeps a variable’s value across iterations of the DATA step. Without it, SAS resets variables to missing at the start of each row. RETAIN is useful when calculating running totals or holding values between rows.

5. What is the function of the N and ERROR automatic variables?

N counts how many times the DATA step has run. ERROR is set to 1 if there’s a problem with an observation; otherwise, it is 0.

Note: SAS interview questions often start with basics like data steps, PROC statements, and key functions used in everyday analysis.

SAS Interview Questions for Freshers

These SAS interview questions and answers are great for beginners who are just starting their career in data analytics or programming.

1. What are the main components of a SAS program?

A SAS program includes three key parts: the DATA step, the PROC step, and statements. The DATA step handles reading, modifying, or creating datasets. PROC steps run built-in procedures like sorting or summarizing. Every statement ends with a semicolon.

2. How do you import data from an Excel or CSV file into SAS?

To import a CSV or Excel file, you can use PROC IMPORT.

Example:

PROC IMPORT DATAFILE=’file.csv’ OUT=work.data DBMS=csv REPLACE;  

RUN;  

In SAS Viya, you can also use point-and-click tools to load data.

3. What are the two types of variables in SAS?

SAS variables are either numeric or character. Numeric variables store numbers used in calculations. Character variables store text like names, IDs, or categories.

4. What is the use of the DATA step in SAS?

The DATA step reads raw data, applies logic, and creates new datasets. You can also filter, create variables, or join data within this step.

5. How is PROC PRINT used in a basic SAS program?

PROC PRINT is used to view a dataset’s content. It displays rows and columns from the dataset. You can also use options like WHERE to filter rows or VAR to show selected columns. It is a quick way to check your data.

Also Read - Top 35+ Data Analyst Interview Questions and Answers

SAS Interview Questions for Experienced

Let’s go through some advanced SAS interview questions and answers for experienced professionals.

6. How do you handle missing values across multiple variables in SAS?

To count or manage missing values, use functions like NMISS (numeric) and CMISS (character). You can also use arrays to loop through variables and set missing values based on logic. For example, recoding all 999s to missing using an array saves time.

7. Explain the difference between MERGE and JOIN in SAS.

MERGE is used in a DATA step and requires sorted data if using BY. It aligns records by position or key. JOIN is done in PROC SQL and works like SQL joins (inner, left, full). MERGE can lead to unexpected results without careful sorting.

8. How do you debug macros in SAS using system options?

Use OPTIONS MPRINT, MLOGIC, and SYMBOLGEN to debug macros.

• MPRINT shows resolved macro code.
• MLOGIC displays macro execution logic.
• SYMBOLGEN reveals the value of macro variables.

These help trace issues step by step.

9. What is the purpose of PROC TRANSPOSE?

PROC TRANSPOSE reshapes data by flipping rows into columns or vice versa. It is useful when converting long data to wide format or summarizing repeated measures. It helps prepare data for reports or modeling.

10. How do you optimize SAS programs for better performance?

I avoid reading unnecessary variables or observations. I prefer WHERE over IF in PROC steps. I also use indexing when working with large datasets. Removing unnecessary sorting and writing clean, modular code keeps it fast and manageable.

SAS Interview Questions for 2 Years Experienced

• How do you merge datasets with different keys in SAS?
• Explain the use of CALL SYMPUT and CALL SYMPUTX.
• Describe a time you had to clean a messy dataset. What was your approach?
• How do you handle tight deadlines when writing SAS reports?
• What do you enjoy most about working with SAS?

SAS Interview Questions for 3 Years Experienced

• How do you decide whether to use PROC SQL or DATA step?
• Share an example of how you reduced processing time in a SAS program.
• Describe a scenario where your SAS output was inaccurate. How did you fix it?
• Why did you choose to work with SAS instead of other analytics tools?
• What is one SAS concept you are currently working to improve?

SAS Interview Questions for 5 Years Experienced

• What are the challenges of handling large datasets in SAS?
• Tell me about a SAS automation you built that saved time.
• Have you mentored junior SAS programmers? What was your approach?
• What motivates you to stay in the data analytics domain?
• What kind of SAS projects do you enjoy the most?

SAS Interview Questions for 10 Years Experienced

• How has your approach to SAS programming evolved over the years?
• Explain your experience with SAS/ACCESS and SAS/CONNECT.
• Describe a high-stakes project where SAS played a critical role.
• What keeps you excited about working with SAS even after 10 years?
• Are you open to learning new tools, or are you more focused on SAS?

SAS Advanced Interview Questions

Here are challenging SAS interview questions and answers that dive deep into complex programming and analytics techniques.

11. What is the use of PROC FCMP and how does it differ from regular SAS procedures?

PROC FCMP lets you create custom functions and CALL routines. Unlike standard procedures, it allows reusable logic you can call within DATA steps. You can define functions using familiar SAS syntax and use them across programs, improving code consistency.

12. How do hash objects work in SAS and when should you use them?

Hash objects store key-value pairs in memory, allowing fast data lookup. They are ideal for joins on small lookup tables or for tasks that require instant access to matching records. They reduce I/O by keeping everything in memory and are initialized in the DATA step.

13. What are the benefits of using PROC DS2 for threaded processing?

PROC DS2 supports multithreaded execution, which means it can split work across multiple CPU cores. It also handles complex data types better than the DATA step and works with multiple database engines. It is useful for heavy data transformations at scale.

14. How do you implement parallel processing in SAS for large datasets?

You can use the THREADS option with PROC SORT, PROC SUMMARY, and PROC MEANS. I also use PROC DS2 and SAS Grid Manager for distributed processing when available. These help speed up jobs that handle millions of records by dividing tasks efficiently.

SAS Technical Interview Questions

Now let’s look at SAS interview questions and answers that focus on technical skills.

15. What is the difference between PUT and INPUT functions in SAS?

PUT converts numeric values to character using a format.

Example: char_var = put(num_var, 8.);

INPUT converts character values to numeric using an informat.

Example: num_var = input(char_var, 8.);

16. How do you use arrays to process multiple variables efficiently?

Arrays allow looping over several variables with fewer lines of code.

Example:

array scores[3] s1 s2 s3;  

do i = 1 to 3;  

  if scores[i] = 999 then scores[i] = .;  

end;  

This helps when applying the same logic across multiple variables.

17. How can you create custom formats using PROC FORMAT?

PROC FORMAT defines value labels without changing data.

Example:

proc format;  

  value agefmt  

    0–12 = ‘Child’  

    13–19 = ‘Teen’  

    20–59 = ‘Adult’  

    60–high = ‘Senior’;  

run;  

You can then apply this format using the FORMAT statement.

SAS Scenario Based Interview Questions

This section covers SAS interview questions and answers based on real scenarios to test your practical thinking and application skills.

18. How would you identify and remove duplicate observations based on multiple variables?

I use PROC SORT with the NODUPKEY option and a BY statement listing all key variables. This removes duplicates based on the combination of those variables. If I need to check all columns, I use NODUP instead.

19. You need to restructure wide data to long format. How would you do it?

I use PROC TRANSPOSE. First, I sort the dataset by ID or group variable. Then I list the variables to transpose in the VAR statement and use ID to create a long format. This works well for survey data or repeated measures.

20. A dataset is missing key values for grouping – how would you impute or fix it?

If values are missing completely, I use PROC STDIZE or set logic in the DATA step based on other variables. For partial missingness, I check previous or next records and fill using RETAIN, LAG, or conditional statements.

Interview Questions for SAS Programmer

Here are some common interview questions for SAS programmer roles.

21. How do you validate your SAS code before sending output to clients?

I run the program line by line and check the log for errors, warnings, or notes. I also compare outputs against known values or prior runs. If possible, I ask a peer to do a code review.

22. What are the key differences between PROC MEANS and PROC SUMMARY?

Both are used to compute descriptive statistics. PROC MEANS prints output by default, while PROC SUMMARY needs the PRINT option. MEANS also analyzes all numeric variables if no VAR statement is used.

23. What steps do you take to clean and prepare raw data in a clinical trial?

I check for missing values, data consistency, and format compliance. I compare raw data to annotated CRFs and protocol rules. Then I derive new variables and create datasets like SDTM or ADaM. I document everything for audit and QC.

Note: Statistical programmer interview questions often cover topics like clinical trial data handling, CDISC standards, and validation techniques.

SAS Admin Interview Questions

These SAS interview questions and answers focus on administration tasks.

24. How do you manage user permissions in SAS metadata server?

I use SAS Management Console to assign roles and access. I define groups, then apply access controls at library, table, or folder levels. I regularly audit permissions to match project needs.

25. What are the key steps in SAS system backup and recovery?

Backups include metadata, configuration files, logs, and data. I schedule regular full and incremental backups. Recovery starts by restoring the backup files, restarting services, and validating the environment before users access it again.

26. How do you monitor and troubleshoot performance issues in SAS environment?

I check CPU, memory, and disk usage using OS tools. I also review SAS logs for long-running jobs. In SAS Environment Manager, I monitor active sessions, latency, and error trends over time.

Other Important SAS Interview Questions

Here are additional SAS interview questions and answers that don’t fit into one category but are often asked in interviews.

Clinical SAS Interview Questions

1. What is SDTM and how is it implemented in SAS?
2. How do you validate SAS programs used in clinical submissions?
3. Explain the process of deriving AE and DM datasets.
4. What are key guidelines in FDA compliance for clinical trial reporting?
5. How do you use PROC REPORT for TLF (Tables, Listings, Figures)?

Clinical SAS Programmer Interview Questions

1. How do you apply CDISC standards using SAS?
2. What are the most common domains in SDTM and ADaM datasets?
3. How do you perform quality checks on derived variables?
4. What is your experience with creating define.xml files?
5. How do you handle unblinding of data in a SAS program?

Base SAS Interview Questions

Here are some commonly asked interview questions on base SAS covering data steps, procedures, and essential functions used in daily tasks.

1. What is the use of PROC CONTENTS?
2. How do you subset data using IF vs WHERE?
3. Explain the use of the LENGTH statement in defining variables.
4. How is the KEEP= option different from the KEEP statement?
5. What is the difference between SET and MERGE?

Interview Questions on SAS Macros

1. What is the difference between CALL SYMPUT and CALL SYMPUTX?
2. How do you pass parameters to a macro?
3. How can you debug a macro using MLOGIC and SYMBOLGEN?
4. What are local vs global macro variables?
5. How do you conditionally execute code within a macro?

SAS Viya Interview Questions

1. How does SAS Viya differ from traditional SAS?
2. What is CAS and how does it function in SAS Viya?
3. How do you load data into memory in SAS Viya?
4. What tools are used to develop and deploy models in Viya?
5. How do you run distributed analytics in SAS Viya?

SAS DI Interview Questions

1. What is the role of SAS Data Integration Studio?
2. How do you design a job to transform raw data into reporting-ready datasets?
3. How is error handling managed in DI Studio?
4. What is the difference between a transformation and a job?
5. How do you schedule jobs in SAS DI Studio?

SAS SQL Interview Questions

1. How do you perform a left join using PROC SQL?
2. What is the difference between calculated and derived variables?
3. How do you count distinct values in a group?
4. What are the performance considerations for PROC SQL vs DATA step merge?
5. How do you update rows in a SAS table using SQL?

SAS VA Interview Questions

1. What are the main components of SAS Visual Analytics?
2. How do you create interactive dashboards in SAS VA?
3. What is auto-charting in SAS VA?
4. How do you manage access control for different users?
5. How is performance optimized in SAS VA?

PROC SQL Interview Questions

1. How do you join more than two tables in PROC SQL?
2. What is the use of the HAVING clause in PROC SQL?
3. How do you create macro variables from PROC SQL?
4. How do you use subqueries in SELECT statements?
5. How do you find duplicates using PROC SQL?

SDTM Interview Questions

1. What is the difference between SDTM and ADaM?
2. What domains are considered essential in SDTM?
3. How do you map raw data into SDTM format?
4. What is the role of controlled terminology in SDTM?
5. How do you validate SDTM datasets?

SAS Interview Questions Asked at Top Companies

Here are company-specific SAS interview questions based on real hiring patterns seen at major employers.

Barclays SAS Interview Questions

1. How do you apply SAS in risk modeling or credit scoring?
2. What is your experience working with large-scale financial datasets?
3. How do you automate daily reporting using SAS?
4. Explain how you would debug an unexpected drop in a key metric.
5. How do you handle sensitive financial data in SAS?

Capgemini SAS Interview Questions

1. Describe a complex ETL job you built in SAS.
2. How do you handle multiple data sources with different formats?
3. What is your approach to peer-reviewing SAS code?
4. How do you handle large SAS batch jobs?
5. What SAS certifications do you hold?

IQVIA Clinical SAS Interview Questions

1. What is your experience with TLF programming?
2. How do you validate SDTM datasets for regulatory submission?
3. What are the key steps in AE domain creation?
4. What are common findings in review of define.xml files?
5. How do you handle protocol deviations in your datasets?

EXL SAS Interview Questions

1. How do you process unstructured data in SAS?
2. What is your experience with SAS EG or SAS Grid?
3. How do you deal with performance bottlenecks in data prep?
4. How do you communicate complex SAS logic to non-technical stakeholders?
5. Explain how you would approach a client data audit using SAS.

GSK SAS Programmer Interview Questions

1. How do you derive key efficacy variables in ADaM datasets?
2. What SAS tools have you used for regulatory compliance?
3. What is the standard naming convention for SDTM datasets?
4. Describe your experience with CDISC standards.
5. How do you QC a derived dataset?

TCS SAS Interview Questions

1. What is your experience with production support in SAS?
2. How do you handle code migration between environments?
3. How do you document SAS projects for long-term maintenance?
4. What is your typical workflow when starting a new SAS project?
5. What is the difference between KEEP= and DROP= dataset options?

How to Prepare for SAS Interview?

SAS roles often need strong programming and analytical skills along with practical project experience. Here are some tips to help you prepare:

• Practice writing clean SAS code from scratch
• Revise key procedures like PROC MEANS, PROC SQL, and PROC TRANSPOSE
• Understand data steps, macro basics, and error handling
• Work on real datasets to gain confidence
• Review log messages to spot issues quickly
• Prepare examples from past projects or coursework

Wrapping Up

So, these are the 30+ SAS interview questions and answers to help you get job-ready. Practicing these questions will improve your confidence and sharpen your SAS skills for real interviews. Stay updated with new features and tools in SAS.

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