SQL Subqueries

1.What is a subquery in SQL?
  • A. A query that runs in a different database
  • B. A query inside another SQL query
  • C. A table inside a query
  • D. A temporary table

A query inside another SQL query

A query inside another SQL query

2.Which keyword is often used with subqueries in WHERE clause?
  • A. GROUP BY
  • B. ORDER BY
  • C. IN
  • D. LIMIT

IN

IN

3.What type of subquery returns only one value?
  • A. Correlated
  • B. Scalar subquery
  • C. Multiple row subquery
  • D. Aggregate query

Scalar subquery

Scalar subquery

4.Which clause does NOT support subqueries?
  • A. WHERE
  • B. FROM
  • C. SELECT
  • D. GROUP BY

GROUP BY

GROUP BY

5.What is a correlated subquery?
  • A. A subquery that runs once
  • B. A subquery that runs row-by-row using outer query values
  • C. A subquery in FROM clause
  • D. A recursive query

A subquery that runs row-by-row using outer query values

A subquery that runs row-by-row using outer query values