set autocommit

Autocommit = {0 | 1} sets whether MySQL transactions are automatically committed. 1 indicates immediate submission, and 0 indicates explicit submission. Global or session is a dynamic variable that can be used in the configuration file (but not in

Mysql lock on the second day, mysql on the second day If there is no lock, the concurrency will be stronger, but the data security will be problematic. Therefore, the database locks the data.Shared lock and exclusive lock That is, the read/write

Details about deadlocks in MySQL and how to handle deadlocks. When multiple transactions hold and request locks on the same resource at the same time and generate a circular dependency, a deadlock occurs. A deadlock occurs when a transaction

The MySQL innodb Storage engine uses the same row lock mechanism as Oracle. The following experiment shows how to view the row locks in the system. The following is the test process:Session 1: update records Mysql> set autocommit = off; Query OK, 0

Developer online builder.com.cn Updated on:2008-02-18Author: heiyeluren Source: csdn Keywords: Test InnoDB Engine MyISAM Engine MySQL [Hardware configuration] CPU: amd2500 + (1.8 GB)Memory: 1 GB/modernHard Disk: 80

ACID: Atomic, Consistent, Isolated, Durable A storage program provides an excellent mechanism to define, encapsulate, and manage transactions. 1. MySQL transaction support 1) MySQL transaction support is not bound to the MySQL server itself, but

Comparison and learning between MySQL and Oracle The storage engine in MySQL is very rich, commonly used include InnoDB, MyISAM, and so on. I also read a lot of information and have some knowledge about it, from some reference books, I can see that

InnoDB modifies the table object structure online Modify the table object structure online: Before MySQL5.6 1. Create a temporary table with the same structure as the original table object (invisible to users by implicit operations) and change the

MySQL index and Optimization Preface: indexes have a crucial impact on the query speed. Understanding indexes is also the starting point for optimizing database performance. Consider the following: Assume that a table in the database has 10 ^ 6

Introduction to InnoDB and MyISAM: This is the default type. It is based on the traditional ISAM type, and ISAM is the abbreviation of IndexedSequentialAccessMethod (sequential access method with indexes, it is a standard method for storing records

Application Analysis based on mysql transactions, views, stored procedures, and triggers bitsCN.com 1. mysql transactions In MYSQL, only INNODB data tables support transaction processing. There are two ways to start a transaction: (1)Use begin,

Understanding MySQL-index and optimization [Reprinted] bitsCN.com Reprinted from: http://www.cnblogs.com/hustcat/archive/2009/10/28/1591648.html Preface: indexes have a crucial impact on the query speed. understanding indexes is also the starting

PHP operates MySQL transaction instances and mysql transaction instances. This article describes how to operate MySQL transactions in PHP. The specific method is as follows: In general, all transactions should be performed in PHP to operate MySQL

This article is mainly to share with you the PHP simple face test Summary, I hope to help everyone. 1. The difference between echo, print, and Print_r: ECHO is a PHP statement that can output one or more strings with no return value. Print,

Now you need to read and insert all contents in the csv file into the database. now you need to read and insert all contents in the csv file into the database. Reply content: Now you need to read all the contents in the csv file and insert it to

Want to use PHP to do a title Web page, novice do not know how to start, before doing a simple upload, but the data only thousands of, now to deal with the millions data import, how to solve. Python But Python is too frustrating to use PHP. Let me

When a thread executes a DELAYED statement on a table, if such a handler does not exist, a processor thread is created to process all the DELAYED statements on the table. When a thread executes a DELAYED statement on a table, if such a handler does

##################### Configurations ##################### Define the name of the backup directory Define (' Backup_dir ', './mybackups '); Define Database Credentials Define (' HOST ', ' localhost '); Define ('

Relationship between autocommit and SQL rollback in mysql bitsCN.com Relationship between autocommit and SQL rollback in mysql. First, I think this answer should be related to autocommit. First, let me explain the background. The problem is repeated:

MySQL common SQL optimization statement bitsCN.com MySQL common SQL optimization statements insert data in large batches. 1. for tables of the Myisam type, you can import a large amount of data quickly using the following methods. Alter table