How do I prepare for a SQL technical interview?

How do I prepare for a SQL technical interview?

If you want to perform well at the SQL job interview, these are the concepts you need to know:

1. Data Definition Language (DDL) keywords.
2. Data Manipulation Language (DML) keywords.
3. Data Control Language (DCL) keywords.
4. Transaction Control Language (TCL) keywords.
5. SQL constraints.
6. JOINs.
7. indexes.
8. transactions.

What are interview questions for SQL?

SQL Interview Questions

• What is Database?
• What is DBMS?
• What is RDBMS?
• What is SQL?
• What is the difference between SQL and MySQL?
• What are Tables and Fields?
• What are Constraints in SQL?
• What is a Primary Key?

Is SQL important for interviews?

SQL programming skills are highly desirable and required in the market, as there is a massive use of Database Management Systems (DBMS) in almost every software application. In order to get a job, candidates need to crack the interview in which they are asked various SQL interview questions.

What will be the output of the below query given an employee table having 10 records?

What will be the output of the below query, given an Employee table having 10 records? BEGIN TRAN TRUNCATE TABLE Employees ROLLBACK SELECT * FROM Employees. This query will return 10 records as TRUNCATE was executed in the transaction.

Where do I prepare SQL queries?

Hop on over to the SQL Practice course on LearnSQL.com. This is the hands-down best place to review and consolidate your SQL skills before a big interview. The course is full of interactive SQL practice exercises that go from easier to challenging.

What is a unique key in SQL?

A unique key is a set of one or more than one fields/columns of a table that uniquely identify a record in a database table. You can say that it is little like primary key but it can accept only one null value and it cannot have duplicate values.

How do I get last 5 rows in SQL?

1. You need to count number of rows inside table ( say we have 12 rows )
2. then subtract 5 rows from them ( we are now in 7 )
3. select * where index_column > 7 select * from users where user_id > ( (select COUNT(*) from users) – 5) you can order them ASC or DESC.

How do I print last 5 rows in SQL?

The following is the syntax to get the last 10 records from the table. Here, we have used LIMIT clause. SELECT * FROM ( SELECT * FROM yourTableName ORDER BY id DESC LIMIT 10 )Var1 ORDER BY id ASC; Let us now implement the above query.

What are the top SQL query interview questions for fresher?

Here is a list of top SQL query interview questions and answers for fresher candidates that will help them in their interviews. In these queries, we will focus on the basic SQL commands only. Ques.1. Write an SQL query to fetch the EmpId and FullName of all the employees working under Manager with id – ‘986’. Ans.

How do I prepare for an SQL data science interview?

Typically, SQL data science interviews ask a range of questions, all the way from basic definition-based SQL questions, to advanced querying exercises and questions. To help you prep for your SQL interview, we’ve curated some of the most common SQL practice problems, exercises and questions (with answers) in a range of categories.

What are some good questions to ask about SQL?

These questions will include understanding the differences between SQL joins, what kinds of aggregations exist, and knowing the basic functions like CASE WHEN or HAVING. Useful definition-based questions for SQL interviews include: Q1. What is a join in SQL? A JOIN is a keyword used to merge together two or more tables on the same key. Q2.

How to improve your SQL skills?

If you want to improve SQL skills, then install a SQL package like MySQL and start practicing with it. To get you started, we’ve outlined a few SQL query questions in this post. Solving practice questions is the fastest way to learn any subject. That’s why we’ve selected a set of 50 SQL queries that you can use to step up your learning.