SQL Server Interview Questions for Dev

Welcome, Dev! As you prepare for your upcoming SQL Server interview, it’s important to be well-versed in the most common questions you may encounter. This comprehensive guide will cover everything you need to know to ace your interview and impress your potential employer.

What is SQL Server?

SQL Server is a relational database management system developed by Microsoft. It is used to store and manage data for a wide range of applications, from small websites to large enterprise systems.

What are the main features of SQL Server?

SQL Server has a wide range of features that make it a popular choice for many businesses. Some of the most important features include:

These are just a few of the many features that make SQL Server a popular choice for businesses of all sizes.

What are the different editions of SQL Server?

SQL Server is available in several different editions, each with its own set of features and pricing. The most common editions are:

There are also developer and web editions available, as well as special editions for various industries.

SQL Server Interview Questions

1. What is a database?

A database is a collection of information that is organized so that it can be easily accessed, managed, and updated. SQL Server is a type of database management system that is used to store and manage data.

2. What is SQL?

SQL, or Structured Query Language, is a programming language used to communicate with databases. It is used to insert, update, and retrieve data from a database.

3. What is a primary key?

A primary key is a unique identifier for a record in a database. It is used to ensure that each record is unique and can be easily accessed.

4. What is a foreign key?

A foreign key is a field in a table that links to the primary key of another table. It is used to establish a relationship between two tables.

5. What is normalization?

Normalization is the process of organizing data in a database so that it is stored in the most efficient and logical manner. It involves dividing larger tables into smaller ones and establishing relationships between them.

6. What is denormalization?

Denormalization is the process of storing data in a less normalized form for faster access. It involves adding redundant data to a table in order to improve performance.

7. What is a stored procedure?

A stored procedure is a pre-written set of SQL statements that can be executed by a user or application. It is used to simplify complex database operations and improve performance.

8. What is a trigger?

A trigger is a special type of stored procedure that is automatically executed in response to a specific event, such as a record being inserted or updated.

9. What is a view?

A view is a virtual table that is based on the result of a SQL query. It can be used to simplify complex queries and provide a user-friendly interface to the data.

10. What is an index?

An index is a data structure that is used to improve the performance of SQL queries. It allows the database to quickly find specific records based on the values in one or more columns.

SQL Server FAQ

1. What is the difference between a clustered and non-clustered index?

A clustered index is created on the primary key of a table and determines the physical order of the data in the table. A non-clustered index is created on one or more columns and contains a copy of the data in those columns, along with a pointer to the location of the full record.

2. What is a deadlock?

A deadlock occurs when two or more processes are waiting for each other to release a resource, such as a locked table or row. This can result in a situation where neither process can proceed, causing the system to become unresponsive.

3. What is a transaction?

A transaction is a series of SQL statements that are executed as a single unit. It allows you to ensure that a group of operations is completed atomically, meaning that either all of the operations are completed successfully or none of them are.

4. What is the difference between a char and varchar data type?

A char data type is a fixed-length string that always takes up the same amount of space, regardless of the length of the string. A varchar data type is a variable-length string that takes up only as much space as necessary to store the string.

5. What is a subquery?

A subquery is a query that is embedded within another query. It is used to retrieve data based on the results of another query.

Conclusion

By studying these common SQL Server interview questions and familiarizing yourself with the features and capabilities of SQL Server, you will be well-prepared to ace your interview and land the job of your dreams. Good luck!