Have you received a job offer from a top-reputed organization? Are you worried about your interview? If yes, then don't worry we are here going to provide you a complete guide on the preparation for the database or SQL interviews. To prepare yourself in advance you can refer to the database interview questions on PostgreSQL, MSSQL, MYSQL, Oracle, etc. It is always good to practice questions to freshen up your skills at least 3 or 4 days before the interview. This increases your chances of selection and you will also sound more confident.
What is SQL
SQL basically refers to the structured query language. SQL is the language that is used in the database management system. You can use it to organize data and entities, and manage relations between different entities of the given data. There is a small difference between SQL and MYSQL which one should definitely know. Where SQL is a standard language MYSQL is a relational database management system, so don't get confused between both of them. There are various constraints in SQL like Default, Foreign key, Not Null, Unique, Index, Check, Primary key, etc.
Topics you must prepare
If you are going for the interview for the first time then there are certain topics that you should definitely cover. Apart from this, it is always recommended to take mock tests to sharpen your skills. Now, we are going to head toward the topics which are mandatory to prepare for your SQL interview.
- You should have knowledge of tables and fields and know how to organize them.
- Go through the definitions of database and DBMS.
- Difference between DBMS and RDBMS.
- Explain different constraints in SQL.
- What do you know about primary keys?
- About joins, views, functions, transactions, locking, stored procedures, table variants
- Difference between the clustered index and non-clustered index.
- Have knowledge about pivoting, updating, or deleting data by using joins, ROW_NUMBER(), RANK(), grouping, etc.
- How to delete duplicate records.
- Difference between SQL and no-SQL databases.
- Examples from real life on SQL and no SQL databases.
- Nested queries
- Normalization, Partition, Acid, and the significance of different keys are also important. Real-life problems in the design
No matter how proficient you are practically in SQL but don't take the interview so lightly. Along with practical knowledge, theoretical knowledge is also important to crack any interview. We have talked about certain topics that you can prepare and can also get sure of your selection by preparing more interview questions on SQL and by giving mocks.
Final Words
For those candidates who are sincerely looking to prepare themselves for the interview, for such students, we are here with the best interview questions app that is easily available. Here you can also get access to mock tests on the relevant topic you are looking for. Apart from this, there are hundred-plus questions with answers to prepare. As you are going for an interview it is important that you know about the uses of SQL and a brief history of it.