Most Frequently Asked Database Administrator Interview Questions and Answers
Practicing a variety of database administrator interview questions can help you land your dream job. If you get selected as a database administrator in any top tech company, your primary duties will include migrating data to the cloud, integrating third-party software, and correcting issues in day-to-day activities.
During your database administrator interview at any FAANG+ company, the interviewer will determine whether you can meet their organization's requirements and help it run smoothly. The interviewer will begin with basic questions before moving on to test your personality to assess your potential and capabilities. Read on to explore some most commonly asked technical and behavioral database administrator interview questions to help you land your dream job.
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Here's what we'll cover:
- Database Administrator Interview Questions and Answers
- Database Administrator Interview Questions on Behavioral Skills
- SQL Server Database Administrator Interview Questions and Answers
- Sample SQL Server Database Administrator Interview Questions for Practice
- FAQs On Database Administrator Interview Questions
Database Administrator Interview Questions and Answers
The employer might ask the following database administrator interview questions to gauge your knowledge about the subject matter, professional and personal character, and problem-solving abilities. Here are a few commonly asked database administrator interview questions and answers.
Q1. What roles does a database administrator perform?
The interview tries to test your knowledge about various roles performed by database administrators by asking such questions. You have to answer in brief and to the point. You have to state that a database administrator plans to install and implement various organization-wide database systems.
Other roles include monitoring the functionality of database resources and evaluating the reviews on the database software. You must mention that a database administrator also looks for securing databases, troubleshooting, and other relevant standards.
Q2. What is the difference between a navigational database and a relational database?
This is one of the most asked database administrator interview questions. In a Navigational DBMS, you should know that each value is associated with another and, most of the time, with no other direct way to access the data. Contrastingly, Relational DBMS uses values common to multiple tables to establish a unique key. By doing this, they make sure there are multiple ways to get to the same place.
Q3. What is a database query?
This is one of the widely asked database administrator interview questions. You should answer this question like an experienced professional to create a strong impact on the interviewer.
A database query is an action that is closely related to some create, read, update, delete (CRUD) function. It is a request to access data from a database to manipulate it or retrieve it. There are several approaches to database query - using query strings, writing a query language, or using a QBE like REST or GraphQL.
Q4. What do update, drop, and insert do?
This is a key question asked in the database administrator interview questions. You must know what all these functions do.
INSERT: It submits data into a database as a new row through a form. Forms take multiple forms or an HTML form. When you click the submit button, it will trigger the built-in form reaction to scan the form of particular fields. This way, it makes sure the required forms are entered correctly.
DROP: It removes a table from a database server or a database. You must know that it’s a dangerous command and must be used only in situations when necessary. Unless you have a backup, you cannot come back from this.
UPDATE: You can modify the values where they meet the criteria using UPDATE. You can either alter rows or a subset using this condition.
Q5. What is the difference between ‘=’ and ‘LIKE’?
When you craft a query or use programming to display data in certain ways, you might get an idea that these can be used interchangeably. In ‘=,’ the value being returned must match the value it is being compared to. However, you can use LIKE with several different parameters, allowing you to be more flexible in your rules.
Q6. What Do You Understand by ODBC?
You can use Open Database Connectivity to make different frontends talk to different data sources (DSNs). You should know that the specifics available depend on certain factors, such as the type of application being used, the backend to which it is being applied, and the driver being used.
Q7. What Do You Understand by a Database Schema?
The database schema is a two-dimensional representation of how each table talks to each other, a way to view the design of a database as a single entity and not as a mixture of tables. They are Visio diagrams with 40 different tables connected through particular columns on either side.
Database Administrator Interview Questions on Behavioral Skills
You must know the position you are applying for. Rehearsing these commonly asked behavioral database administrator interview questions can help you create a strong image in front of the interviewers.
- How will you help a client get the best SQL Server?
- As a database administrator, how do you prevent data loss?
- What database tools do you use?
- How do you handle complaints about database performance from users?
- Share your experience with cloud databases?
- What is your daily routine as a database administrator?
- Explain how you troubleshoot database issues?
- Briefly describe your experience with Hadoop?
- I have a database built in MySQL, and I need the data to be moved over to Microsoft SQL Server. How would I do this?
- Have you had any bad experiences while running a test on a live database?
- How would you store files within a database?
- Why do database servers benefit from a lot of memory, and why do 64-bit operating systems help in this regard?
- Why is it difficult to use standard file-by-file backup methods on an active database server?
Recommended Reading: Top Database Interview Questions You Should Prepare for Technical Interviews
SQL Server Database Administrator Interview Questions and Answers
Below are the most expected SQL Server database administrator interview questions for experts and beginners. You must master these questions thoroughly to grab the best job in the top FAANG or other tech companies.
Q1. What is SQLOS?
This is the basic question asked in the SQL Server database administrator interview. You must answer this question like an experienced professional.
SQLOS stands for SQL Server Operating System. It works like a mini operating system for SQL Server operations. It is the lowest layer of the SQL Server database engine, which performs critical internal tasks, like memory management, scheduling threads on the CPU to execute SQL Server transactions, deadlock detection, and IO completion activities.
Q2. Compare SQL Server with Oracle.
You should know the key differences between SQL Server and Oracle if you prepare SQL Server database administrator interview questions and answers. The comparison between them is given in the table.
Take a look at the top Oracle DBA Interview Questions for better prep for your tech interview.
Q3. Can we add a CPU to SQL Server?
Yes, you can add CPU to SQL Server by adding new hardware. You can do this logically by hardware partitioning or virtually through a virtualization layer. You should be aware that from 2008 onwards, the SQL Server version supports CPU Hot Add. Below are the requirements to use CPU Hot Add:
- SQL Server enterprise
- 64-bit Windows Server 2008 Datacenter or Windows Server 2008 Enterprise Edition for Itanium-based system OS
- Hardware that supports CPU Hot Add
Q4. What are the common trace flags used with SQL Server?
The common trace flags used in SQL Server are:
- Disable Locking Hints: 8755
- Log Record for Connections: 4013
- Deadlock Information: 1204, 1205, and 1222
- Forces uniform extent allocations instead of mixed page allocations 1118 (SQL Server 2005 and 2008) to reduce TempDB contention
- Network Database Files: 1807
- Skip Startup Stored Procedures: 4022
Q5. How to upgrade SQL Server 2000 to SQL Server 2008?
The safest way to upgrade SQL Server 2000 to SQL Server 2008 is a side-by-side upgrade. You can do this by detaching/attaching the database files or using the backup and restore option. However, the latter is safer than the former. You have to perform the following steps to upgrade the SQL server:
- First, you have to run the upgrade analysis tool from Microsoft. After that, address the issues raised.
- You need to identify the DTS packages.
- Then rebuild the DTS packages as SSIS.
- You have to script out all SQL Agent jobs.
- Then, script out all security.
- After that, backup the systems and validate the backups.
- You need to run the security script on the new system.
- Run restore on the new system.
- Validate the databases by running DBCC.
- Manually update all statistics.
- Finally, you have to run the SQL Agent script.
Sample SQL Server Database Administrator Interview Questions for Practice
- How can we check whether the port number is connecting or not on a Server DBA?
- What is Extent?
- How can you start SQL Server in different modes?
- What different steps will a SQL Server Developer take to secure SQL Server?
- How to create a database with a specific file location?
- What are Hotfixes and Patches?
- List the backup types.
- What are the methods for backup?
- What services are available along with SQL Server?
- How to decide between active and passive nodes?
- Why is SHRINKFILE/SHRINKDB/AUTOSHRINK not preferable?
- Can you detach SQL Server 2005 database and attach it to SQL Server 2008?
- Why would you use SQL Agent?
- How can you control the amount of free space in your index pages?
- What authentication modes does SQL Server support?
- What are the different SQL Server Versions you have worked on?
- How many files can a Database contain in SQL Server? How many types of data files exist in SQL Server? How many of those files can exist for a single database?
- Where do you find the default Index fill factor, and how to change it?
- What happens at the checkpoint?
- Which third-party tools are used in SQL Server, and why would you use them?
- What is a correlated subquery?
- How do you trace the traffic hitting a SQL Server?
- What are the different Topologies in which Replication can be configured?
- How do you get I/O statistics of a specific database file like the number of reads, writes, IO stalls, etc.?
- What is Automatic Seeding in Always on availability groups?
- Which action plan is preferred if SQL Server is not responding?
- What is Enhanced Database Failover in the Always-on availability group?
- Why would you call Update Statistics?
FAQs On Database Administrator Interview Questions
Q1. What are the topics mostly asked in the SQL Server Database Administrator Interview Questions?
The interviewer will test your experience by asking a mixture of basic and advanced SQL Server database administrator questions. They will ask about the purpose of the model database server, your experience with the SQL Server DBA, what replication and DCL are, different types of recovery models and their importance, ways to create databases in SQL Server, and more. So, you must prepare the SQL Server database administrator interview questions mentioned above to crack your tech interview.
Q2. A client needs a SQL server. What questions do you ask them to determine the right one?
These types of database administrator interview questions are asked to demonstrate your server knowledge and how you will interact with the customers. You have to tell the interviewer that you will ask what type of SQL the client could support as the SQL must suit the organization's size. You will check whether a backup has been generated or not. After that, if the old database is not compatible with the new one, you will upgrade the old version to an intermediate one and then upgrade the current server to resolve the issue.
Q3. How to prepare for a DBA interview?
You have to go through the job description first. Look into what the company demands. Then, you have to fit into the shoes and prepare every answer that matches the candidate the company is looking for. You can start preparing by reading the most anticipated database administrator interview questions mentioned above. Later on, you can practice behavioral questions before your known ones to gain confidence and enhance communication skills.
Q4. What is the average database administrator salary in the US?
The database administrator's salary depends on various factors, such as location, company, experience, skills, and background. The average database administrator salary in the US is $90,681/ year (source: indeed.com). Companies such as Apple, EY, Oracle, TCS, Spectrum, and others provide the finest salaries to their database administrators. The average salaries in these companies range between $150,000 to $95,000. Moreover, cities like Dallas, New York, Phoenix, Chicago, and others, offer top salaries to the DBAs.
Q5. How to become a database administrator?
You must have a bachelor's degree in information technology or computer science to become a database administrator at entry-level positions. If you have a master's degree, you will be prioritized in complex or experienced job positions. However, having a profound knowledge of databases, how they work, and how to resolve the problems will help you become an efficient database administrator.
Gear Up for Your Next Tech Interview
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