MySQL

MyISAM lock Mechanism:MyISAM only table locks, divided into X and S lock two (or called read Lock,write Lock). Read Plus s lock, write plus x lock. Blocking each other, so concurrent DML performance is not good. InnoDB lock Mechanism:Lock

This section relates to: Create a database, view a database, modify a database, delete a database Starting Time: 2018-02-13 20:47Create DATABASE: Syntax:Create database name [ library option ];Library Options Description: Library options

In this article, I demonstrate how to configure the MySQL group replication multi-Master model (multi-primary). In the configuration, the group replication and the single master model of the multi-master model are basically no different.This article

A chance, show processlist time, found a Client has been executing "mysql-connector-java-5.1.21 (Revision: ${bzr.revision-id}) */show Varia Bles WHERE variable_name "After the discussion with the base friends, a little bit of a wisp. Probably the

Students with MySQL experience may encounter SQL slow query scenarios in the actual project, some scenarios are easy to locate the problem (such as a single table operation with slow query SQL, carefully check SQL statements are usually easy to

Stored procedures:Delimiter| Create procedureGet_product_info (inchIMiDint(Ten),intIuservarchar( -))begin Select * fromTb_testwhereMid=IMiD and User =Iuser;End;|delimiter;Python calls:ImportMysql.connector CNX= Mysql.connector.connect

Now the software is more and more good to install, especially in Ubuntu under the installation of software, there is no skill, just need to use apt-get inatll in the case of networking. Before you decide to install MySQL, determine if the system

A lot of friends in the tuning with MySQL will certainly use the explain to see the execution of the SELECT statement, here is a brief introduction to the results of the meaning of the two columns.1 Type column The official saying that this column

MySQL templates, which are used online in this address http://mysql-cacti-templates.googlecode.com has not been accessedGoogle found this URL:Introduction Cheat:

1. Preface MySQL is a fully networked cross-platform relational database system and a distributed database management system with a client/server architecture. It has the advantages of strong functions, ease of use, convenient management, fast

1. Why back up the database? Backup is the most important and easy to ignore for databases. Unexpected events may cause serious losses. The more important the data is, the more frequently the data changes, and the more frequently backup is

MySQL command line export and import database, mysql command line Database For example, we will introduce how to use the command line to export and import MySQL data to a database. 1. Export Database through command line 1. Go to the bin folder

The differences between com. mysql. jdbc. Driver and com. mysql. cj. jdbc. Driver, Overview: com. mysql. jdbc. Driver is in mysql-connector-java 5, while com. mysql. cj. jdbc. Driver is in mysql-connector-java 6.1. JDBC to connect to Mysql5 requires

MySQL index details, MySQL index detailsI. Introduction to index basics 1.1 In MySQL, indexes are also called keys. They are a data structure that the storage engine uses to quickly find records. Indexes are critical to good performance. Especially

MYSQL database in PHP and mysql databaseMYSQL database Introduction 1. What is a database? A database is an ordered set composed of a batch of data. This set is usually saved as one or more files related to each other. 2. What is a relational

The following articles mainly introduce how to use MySQL built-in functions to convert IP addresses and related numbers. In actual operations, when processing character formats, such as converting 54789, we only need to use: format (12345, 0). The

The following article describes how to connect the MySQL client to a remote database server. In general, we are used to installing MySQL databases on a personal computer, then I used SQLyog and other client software to connect. Today I tried to

Differences between MySQL and SQL Server 1. mysql supports enum, set, and SQL server.2. mysql does not support nchar, nvarchar, and ntext3. the incremental Statement of mysql is AUTO_INCREMENT, while that of mssql is identity)4. mssql by default,

MySQL 7-1-Stored Procedure 1. advantages of using Stored Procedure: (1) the stored procedure runs on the server and runs fast. (2) After a stored procedure is executed once, the execution plan will reside in the cache. In future operations, you only

In MySQL, what is the maximum length of the varchar type? We will find that the varchar length is 65535 for the varchar data type, that is, 65532 bytes of data can be stored, is that true? Let's take a look. 1. Restrictions Field restrictions