What do you understand by a subquery? When is it used? – InterviewSolution

InterviewSolution

1.	What do you understand by a subquery? When is it used?
Answer» A subquery is a SELECT statement embedded in a clause of another SELECT statement. It is used when the inner query, or the subquery returns a value that is used by the outer query. It is very useful in selecting some rows in a table with a condition that depends on some data which is contained in the same table.

Discussion

No Comment Found

Related InterviewSolutions

Say True or False. Give explanation if False.A view doesn’t have data of its own.
What is a view? Why should you use a view?
Which SQL statement is used to add, modify or drop columns in a database table?
Say True or False. Give explanation if False.A DROP TABLE statement can be rolled back.
What is the difference between VARCHAR2 AND CHAR datatypes?
Say True or False. Give explanation if False.A DDL statement or a DCL statement is automatically committed.
What is the purpose of the MERGE statement in SQL?
Say True or False. Give explanation if False.You can use a subquery in an INSERT statement.
Say True or False. Give explanation if False.Attempting to delete a record with a value attached to an integrity constraint, returns an error.
Can you remove rows from a table based on values from another table? Explain.