What are HEAP tables in MySQL?

Interview Questions

MySQL and SQL

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.

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Other Interview Questions

What's MySQL
What is DDL, DML and DCL?
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Database Basics
MySQL Command Interpreter
Installing a MySQL Binary Distribution
MySQL - Quick Installation Overview
MySQL - MySQL Extensions to ANSI SQL92
MySQL - Running MySQL in ANSI Mode
Functionality Missing from MySQL - Sub-selects
Functionality Missing from MySQL - SELECT INTO TABLE
Functionality Missing from MySQL - Transactions
Functionality Missing from MySQL - Stored Procedures and Triggers
Functionality Missing from MySQL - Foreign Keys
MySQL - Reasons NOT to Use Foreign Keys constraints
Functionality Missing from MySQL - `--' as the Start of a Comment
Functionality Missing from MySQL - How to Cope Without COMMIT/ROLLBACK
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How to Make MySQL Secure Against Crackers
MySQL - Startup options to mysqld which concerns security
MySQL - What the Privilege System Does
MySQL - User Names and Passwords
How to connecting to the MySQL Server
MySQL - Keeping Your Password Secure
Privileges Provided by MySQL
MySQL - How the Privilege System Works
MySQL - Access Control, Stage 1: Connection Verification
MySQL - Access Control
MySQL - When Privilege Changes Take Effect
Setting Up the Initial MySQL Privileges
Adding New User Privileges to MySQL
MySQL - Setting Up Passwords
MySQL - Causes of Access denied Errors
Replication in MySQL
MySQL - Replication Implementation Overview
MySQL - how to set up complete replication on your current MySQL server
MySQL - Replication Features and known problems
MySQL - SQL Commands Related to Replication
MySQL - Why do I sometimes see more than one Binlog_Dump thread on the master after I have restarted the slave?
MySQL - How do I rotate replication logs?
MySQL - How do I upgrade on a hot replication setup?
MySQL - What issues should I be aware of when setting up two-way replication?
MySQL - How can I use replication to improve performance of my system?
MySQL - What should I do to prepare my client code to use performance-enhancing replication?
MySQL - When and how much can MySQL replication improve the performance of my system?
MySQL - How can I use replication to provide redundancy/high availability?
MySQL - Troubleshooting Replication
How to get Maximum Performance from MySQL
MySQL - Optimization Overview
MySQL - System/Compile Time and Startup Parameter Tuning
MySQL - Disk Issues
MySQL - Using Symbolic Links for Databases and Tables
MySQL - Tuning Server Parameters
How MySQL Opens and Closes Tables
MySQL - Drawbacks to Creating Large Numbers of Tables in the Same Database
MySQL - Why So Many Open tables?
How MySQL Uses Memory
How MySQL Locks Tables
MySQL - Table Locking Issues
How MySQL uses DNS
MySQL - Get Your Data as Small as Possible
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