MySQL Tutorials - Herong's Tutorial Examples - Version 4.20, by Dr. Herong Yang

MySQL Tutorials - Herong's Tutorial Examples

∟Locks Used in MySQL

∟Lock Types and Lock Levels

There are two types of locks:

• Read Lock - The locked data is reserved for read by the current session. Other sessions can read the locked data. But they can not write (update) the locked data. A read lock is also called a shared lock.
• Write Lock - The locked data is reserved for write by the current session. Other sessions can not read and write the locked data. A write lock is also called an exclusive lock.

There are three levels of locks:

• Table Lock - The lock is set at the table level. All rows in the locked table are locked.
• Row Lock - The lock is set at the row level. Some rows of a table are locked. But other rows are not locked.
• Column Lock - The lock is set at the column level. Some columns of a row are locked. But other columns are not locked.

Last update: 2015.

Table of Contents

 About This Book

 Introduction of SQL

 MySQL Introduction and Installation

 Introduction of MySQL Programs

 Perl Programs and MySQL Servers

 PHP Programs and MySQL Servers

 Java Programs and MySQL Servers

 Datatypes and Data Literals

 Operations and Expressions

 Character Strings and Bit Strings

 Commonly Used Functions

 Table Column Types for Different Types of Values

 Using DDL to Create Tables and Indexes

 Using DML to Insert, Update and Delete Records

 Using SELECT to Query Database

 Transaction Management and Isolation Levels

►Locks Used in MySQL

►Lock Types and Lock Levels

 Table Level Locks in MySQL

 Row Level Locks in MySQL

 Defining and Calling Stored Procedures

 Variables, Loops and Cursors Used in Stored Procedures

 Outdated Tutorials

 References

 PDF Printing Version

Lock Types and Lock Levels - Updated in 2015, by Dr. Herong Yang