Explanation:The subquery (SELECT AVG(salary) FROM employees) calculates the average salary. The outer query returns employees whose salary is greater than this average. 15. LEFT JOIN to Include Nulls Question: Write a query to list all employees and their department names, including employees who ...
EXISTS Returns TRUE if query matches at least one row in set 10. What have you used SQL for in past jobs? This one is a softer question, but no less important than the others listed on this page! If you're walking into an SQL interview, you're bound to be asked about your prior...
SQL stands for Structured Query Language , and it is used to communicate with the Database. This is a standard language used to perform tasks such as retrieval, updation, insertion and deletion of data from a database. 7. What is a unique key? A Unique key constraint uniquely identified e...
SQL (Structured Query Language) Interview Questions And AnswersSharpen your SQL interview expertise with our handpicked 172 questions. Each question is crafted to challenge your understanding and proficiency in SQL. Suitable for all skill levels, these questions are essential for effective preparation. ...
After we run the query our table will look like this:ConclusionSQL is a high-demand skill today and a language that should not be missing from the arsenal of programmers. This guide listed out a few of the most asked SQL interview questions and gave their answers to begin with, to keep...
4. What are the steps you will take to improve performance of a poor performing query? This is a very open ended question and there could be a lot of reasons behind the poor performance of a query. But some general issues that you could talk about would be: No indexes, table scans, ...
What is a query?A DB query is a code written in order to get the information back from the database. Query can be designed in such a way that it matched with our expectation of the result set. Simply, a question to the Database....
How do we know if a query is retrieving a large amount of data or very little data?DBA question By using the "Client Statistics" feature in SSMS.Day13 What is the difference between GRANT and WITH GRANT while giving permissions to the user? (GRANT is giving you permission to do something...
article i will try to explain most important PL/SQL Interview Questions that may ask in interview.PL/SQL is the Procedural Language Structured Query Language which will use to add the business logic. In this article I will try to give the brief description about different PL/SQL interview ...
SQL在2021年的数据方向面试中目前大部分只存在于phone interview（电话面试）当中，在onsite interview（...