MySQL

Recently in the study of MySQL, of course, the first to install it on the machine. Record the operation, deepen the memory, also for later reference.Preparatory work:Linux version:Redhat Linux 6.4MySQL version (installation package):

Database:Create Database|schema [if not exists] db_name [Character set =] [collate =];ALTER DATABASEDrop {database | schema} [if exists] db_name;Table:1, directly define an empty table;2, from other tables to query the data, and create a new table;3.

#!/bin/sh # MySQL Data backup script # # Use mysqldump--help,get more detail. # Bakdir=/root/back/mysql Logfile=/root/back/mysql/mysqlbak.log Date= ' Date +%y%m%d%h%m%s ' echo "" >> $LogFile echo "" >> $LogFile echo "---

Mysql_affected_rows: Gets the number of columns affected by MySQL last operation.Mysql_close: Close the MySQL server connection.Mysql_connect: Open the MySQL server connection.mysql_create_db: Create a new MySQL database.Mysql_data_seek: Moves the

Mathematical functionsAbsolute ABS ()Pi ()Square root sqrt ()Modulo to remove the remainder mod (dividend, divisor)Random number rand ()Rounding Round (number)Second party POW (5,2)E is the bottom exponent function exp (number)String functionsLength

InnoDB Index Concept   Summary record InnoDB index concepts for viewing INNODB index classification: Clustered index (clustered index)     1)   When a primary key is available, a clustered index is created from the primary key     2)   when there is

#!/bin/bash#MySQL备份dates= ' Date +%y%m%d 'datey= ' date-d ' days Ago "+%y%m%d"Mkdir-p/home/backupCd/home/backupMysqldump-uroot-pwyqj_root fight_cancer > Fight_cancer. $dates. sqlMysqldump-uroot-pwyqj_root redmine > Redmine. $dates.

Download MySQL database: http://dev.mysql.com/downloads/mysql/, unzip to localDownload jar package: http://dev.mysql.com/downloads/connector/j/, download zip archive packageCreate a database and insert several data:Create TableMyDB; UseMyDB;Create

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 --存储过程名和参数，参数中in表示传入参数，out标示传出参数，inout表示传入传出参数create procedure p_procedurecode(in

1. Create a Java project in Eclipse 2. Introduce the JDBC Library (in extenrnal of bulid path) 3. 1) import the SQL package (import java. SQL .*) 2) load (Register) the mysql jdbc driver Class. forName ("com. mysql. jdbc. Driver "); 3) connect to

Show [session | global] status you can add the parameter "session" or "global" as needed to display the session-level (current connection) statistics and global-level (since the last time the database was started). If this parameter is not specified,

Start MySQL 1. initialization module execution & initial storage engine execution 2. After the execution is completed in step 1 ----> the connection management module takes over 3. The connection management module starts the listening program

Mysql provides three installation methods: binary, rpm, and source code compilation. Here we will discuss in detail how to compile and install mysql source code. Mysql does not support configure compilation after version 5.5. Instead, it uses the

LNMP1.0 can be used to quickly build a PHP environment in a Linux system. Previously, the LNMP environment has been used to operate other servers, and similar errors have not been detected. Now we will record the solution process. I. server

We all know that com_insert and other com_xxx parameters can be used to monitor the access volume of database instances, which is what we often call QPS. Based on the MySQL replication principle, all operations performed by the master database are

Scenario:Master database DB: utf8 Character SetSlave database DB: gbk character set Requirements:Verify that the master and slave data are consistent and repair Verification process:Set the master database connection to utf8, set the slave database

Mysql release result memory sample code Definition and usage The mysql_free_result () function releases the result memory. If the operation succeeds, true is returned. If the operation fails, false is returned. Syntax Mysql_free_result (data)

Mysql Stored Procedure in END compound statement usage example Begin_label:] BEGIN [Statement_list] END [end_label] You can use the in... END compound statement to store subprograms to contain multiple statements. Statement_list indicates the

Mysql uses the WKB function to create Geometry (ry) Values MySQL provides many functions that use BLOB containing WKT expressions or optional Spatial Reference System ID (SRID) as input parameters. They return corresponding geometric

Mysql database KEY partition usage Partitioning by KEY is similar to partitioning by HASH. Except for the User-Defined expression used by HASH partition, the HASH function of KEY partition is provided by the MySQL server. MySQL Cluster uses the MD5