Which is often faster for existence checks on large, indexed tables?

Problem Statement

Explanation

EXISTS can stop on the first match and leverage an index on the right table. That avoids duplicate inflation and extra sorts. JOIN plus DISTINCT may add more work because the left row can multiply before being deduplicated.

Code Solution

SolutionRead Only

SELECT c.id FROM customers c
WHERE EXISTS (
  SELECT 1 FROM orders o WHERE o.customer_id=c.id AND o.total>0
);

Practice Sets

This question appears in the following practice sets:

Subqueries & CTEs (incl. Recursive)

Next Question

Master Interviews
Anywhere, Anytime

Which is often faster for existence checks on large, indexed tables?

Problem Statement

Explanation

Code Solution

Practice Sets

Related Questions

Which SQL statement retrieves all columns and rows from a table named employees?

Which clause filters rows before aggregation and affects which rows are grouped?

What is the default sort order when ORDER BY is used without ASC or DESC?

Which construct is commonly used to paginate results in SQL engines like Postgres and MySQL?

Which predicate correctly checks for missing values in standard SQL?

More from SQL & Databases

Master Interviews Anywhere, Anytime

Which is often faster for existence checks on large, indexed tables?

Problem Statement

Explanation

Code Solution

Practice Sets

Related Questions

Which SQL statement retrieves all columns and rows from a table named employees?

Which clause filters rows before aggregation and affects which rows are grouped?

What is the default sort order when ORDER BY is used without ASC or DESC?

Which construct is commonly used to paginate results in SQL engines like Postgres and MySQL?

Which predicate correctly checks for missing values in standard SQL?

More from SQL & Databases

Master Interviews
Anywhere, Anytime