theparthee
Explain the difference between SINGLE JOIN and MULTIPLE JOIN.
Last Updated: December 2, 2025The difference between a single join and a multiple join in SQL mainly comes down to how many tables you’re...
How do you retrieve the current date and time in SQL?
Last Updated: December 2, 2025To retrieve the current date and time in SQL, I use built-in date functions — the exact function name can...
What is the difference between CHAR and VARCHAR in SQL?
Last Updated: December 2, 2025The main difference between CHAR and VARCHAR in SQL lies in how they store data and handle storage space. CHAR...
What is a correlated subquery?
Last Updated: December 2, 2025A correlated subquery is a type of subquery that depends on the outer query for its values — meaning the...
How do you select rows with a specific condition using HAVING?
Last Updated: December 2, 2025To select rows with a specific condition using HAVING, I use it when I’m dealing with aggregate functions like SUM,...
What is a self-join?
Last Updated: December 2, 2025A self-join is when a table is joined with itself — basically treating the same table as if it were...
What is normalization in SQL?
Last Updated: December 2, 2025Normalization in SQL is the process of organizing data in a database to reduce redundancy and improve data integrity. In...
Explain the use of COMMIT and ROLLBACK in SQL.
Last Updated: December 2, 2025COMMIT and ROLLBACK are two key transaction control commands in SQL that ensure data consistency by managing how and when...
What are transaction control commands in SQL?
Last Updated: December 2, 2025Transaction control commands in SQL are used to manage changes made by DML operations like INSERT, UPDATE, and DELETE. They...
How do you update multiple columns in SQL?
Last Updated: December 2, 2025To update multiple columns in SQL, I use the UPDATE statement with the SET clause, where I can assign new...