---
title: "What are HEAP tables in MySQL?"  
description: "What are HEAP tables in MySQL?"  
author: "Sumit Kesarwani"  
published: 2014-02-10  
updated: 2020-09-23  
canonical: https://www.mindstick.com/interview/1914/what-are-heap-tables-in-mysql  
category: "mysql"  
tags: ["mysql"]  
reading_time: 1 minute  

---

# What are HEAP tables in MySQL?

HEAP tables are in-memory. They are usually used for high-speed temporary storage.

No TEXT or BLOB fields are allowed within HEAP tables.

You can only use the comparison operators = and ‹=›.

HEAP tables do not support AUTO_INCREMENT.

Indexes must be NOT NULL.

## Answers

### Answer by Sumit Kesarwani

HEAP tables are in-memory. They are usually used for high-speed temporary storage.

No TEXT or BLOB fields are allowed within HEAP tables.

You can only use the comparison operators = and ‹=›.

HEAP tables do not support AUTO_INCREMENT.

Indexes must be NOT NULL.


---

Original Source: https://www.mindstick.com/interview/1914/what-are-heap-tables-in-mysql

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