MySQL

from table name; name of the TRUNCATE table;The DELETE statement without the Where parameter removes everything from the MySQL table, and you can also empty all the contents of the MySQL table using TRUNCATE table. The efficiency of truncate is

Starting with the CENTOS7 version, in order to maintain a better open source, the system minimized version of the default database becomes MARIADB, but in order to experiment, the decision to install MySQL (after all, the storage engine is different,

The first is the installation of the environment: 1. Install Python2.7, do not install version 3.5, because many dependent libraries do not support the latest version 2. Install robot framework,databaselibrary,pyodbc,selenium2library,appiumlibrary

First of all, Centos7 is a pit daddy.Next, install MySQL on the centos7 more pit daddy.This is the only way to record a pit-daddy journey.Install MySQLwget http://repo.mysql.com/mysql-community-release-el7-5-ivh mysql-community-release-el7-5. Noarch.

There are tables, a, B, Name,sal,deptno1, Data UpdateUpdateUpdate A set sal=500 where name= ' Zhangsan ';(can change multiple values at once, separated by commas)2, deletion of dataDeleteDelete from A where name= ' Zhangsan ';(delete a row of

1. View by Function database ()mysql> SELECT database ();650) this.width=650; "src=" Http://s5.51cto.com/wyfs02/M01/80/20/wKioL1c5OQHAujQZAAAMC4M3jFw898.png "title=" 1.png " alt= "Wkiol1c5oqhaujqzaaamc4m3jfw898.png"/>2. View by Statusmysql> status;65

What is the storage engineFor example, if you are working on a large amount of temporary data, you may need to use a memory storage engine. The memory storage engine can store all the tabular data in memory. Alternatively, you might need a database

1. When working on a transaction, if it is found that the current transaction operation is unreasonable, as long as the transaction has not been committed, it can be rolled back to cancel the current transaction, followed by a detailed explanation

1. Introduction of the concept of transactions:In real life, we often do transfer operations, transfer operations can be divided into two parts to complete, transfer and transfer out. Only these two parts are complete before you can consider the

First, let's talk about the project scenario:1: This is a web-based Java project, its main function is to some of the audio and video information processing and display, wherein the audio data is crawled by the crawler crawl Tens amount of data2:

Note: The field after select must either be included in group by or be included in the aggregate function after having a. 1. Group BY is a group query, and the general group by ISuse with aggregate functionsGroup by has a principle that all columns

1. On the MySQL side (Zabbix client) modifying parameters for monitoring MySQL[Email protected] ~]# VIM/ETC/MY.CNF[MySQL]Auto-rehashuser= User Namepassword= Password[Mysqladmin]user= User Namepassword= Password [[email protected] ~]#

ObjectiveAfter the installation of MySQL, there must be some tuning of MySQL's various parameter options. Although the MySQL system is highly scalable, it can run efficiently in a very sufficient hardware resource environment, and can operate well

1. Natural connection Using MySQL's own judgment to complete the connection process without specifying a connection condition, MySQL uses the same fields from multiple tables as the join condition. Internal connection natural Join

Select CONCAT ("Mysqldump-uroot-p", Table_schema, "", TABLE_NAME, ">>", Table_schema, ". Bak.sql")From INFORMATION_SCHEMA WHERE table_name like ' country% ';You can also save the generated shell command in a file (but it must be a local folder, or

The installation of MySQL Mac took some effort. Initially want to save trouble with brew installation, the result is always a problem, the original brew installation MySQL is not so simple, but also some configuration. Simply go to the website to

1 Downloads Download website Choose the Community Free Edition Platform Linux Genitic Version 64-bit, my virtual machine is 64-bit 2 installation Upload

Recently in the configuration of MySQL master-slave test, always repeat the installation of MySQLSo make a script, the MySQL process is to refer to someone else'sBut the shell wrote it himself.#!/bin/bash#切换到下载目录Cd/usr/local/src#下载免免编译的包wget

How to remotely back up MySQL binlog and mysqlbinlog Previously, binlogs were backed up and compressed locally, and then sent to a remote server. However, there are still some risks, because log backup is cyclical. If the server goes down and the

Mysql found_row () Usage Details, mysqlfound_row Mysql found_row () is used to obtain the number of rows obtained by the Select statement. For example, a SQL statement needs to retrieve the first 10 rows of a table and the total number of rows that