SQL interview questions: top 15 questions in 2022

What is? SQL, Why is it important ？

Structured query language (SQL) Is a query language that allows you to create complex queries . It's a programming language , Used to manage data in a relational database . It can handle distributed databases , It provides users with many choices .SQL Allow users to access information stored in a relational database management system .

Who will face SQL problem ？

SQL For changing and communicating with the database , Enable enterprises to better access data . Business Analyst 、 Software engineer 、 Both system administrators and data scientists use SQL, So knowing it will make you an attractive employee . therefore , If you are working as a database administrator 、 Business Analyst 、 Software engineer 、 The profession of system engineer , Or you are looking for SQL Internship opportunities in the field , So you've come to the right place . Before viewing these 15 individual SQL Interview questions and answers , Be prepared to make the most of the interview .

15 A question and an answer

1. What is? SQL（ Structured query language ）？

visit 、 The standard language for updating and manipulating relational databases is SQL Or structured query language . Users can use this tool to filter... From a relational database 、 Sort and extract data .

2. What is basic SQL Query element ？

Of course , Every SQL The specific structure of the query will depend on the problem you are trying to solve . However , majority SQL Queries are made up of several basic parts .SELECT、FROM、JOIN、WHERE、GROUP BY、HAVING and ORDER BY It's all typical SQL Query element .

3、SQL Medium WHERE What is a clause ？

stay FROM or JOIN After statement , Use WHERE. It only returns records that meet the specified conditions . Comparison operator (Age > 21) And logical operators (Name NOT ‘Jane’) can