MySQL

[Root @ centos MySQL] # groupadd MySQL[Root @ centos MySQL] # useradd-G MySQL Compilation and Installation Tar-zxvf mysql-5.1.35.tar.gz ./Configure \-- Prefix =/usr/local/MySQL \-- Localstatedir =/data/MySQL/data \MySQL DATA DIRECTORY-- Enable-

If the root password is not set during installation, you can directly press Enter when logging on using the MySQL command line tool. However, you must set a password when connecting some tools. The simplest method: Go to the bin directory of the

Command for backing up MySQL database Mysqldump-hhostname-uusername-ppassword databasename> backupfile. SQL Back up the MySQL database in the format of a table with deletion Backing up a MySQL database is in the format of a table with deletion,

The mysql client I use in Windows is mysql-front. Unfortunately, the for linux version is not available, and the update has not occurred for a while. However 《ProgramClerk magazine saw the news that the new version of workbench has been released. In

I use MySQL 4.1.20. I always thought that when a table lists the order by statements of the current query statement, MySQL uses this index if this column is indexed. It is not until now that this is a mistake. I have tracked databases over the

The error code table of MySQL is compiled according to the MySQL/include/mysqld_error.h header file. Correct the error.1005: An error occurred while creating the table.1006: database creation failed1007: the database already exists. An error

Use of mysqldumpTo use mysqldump for database backup, you must run the bin directory under Doc in windows.If you only want to back up a table structure and discard the relevant data. As follows:Mysqldump daocs da_card_pwd-uroot-p-D> D:/dbupdate2.

I. MySQL service operations1. Net start mysql41 // start the MySQL Service 2. net stop mysql41 // stop MySQL Service 3. mysql-H host address-u user name-P User Password // enter the MySQL database 4. Quit // exit MySQL 5. mysqladmin-u username-P old

I. SQL ServerObtain N records from the M records in the database table. Use the top Keyword: Note that if the SELECT statement contains both top and order by, select from the sorted result set:Statement format:Select top 10 *From testtableWhere (ID>(

Refer: [1] http://www.codesky.net/article/201010/147160.html 1. Create a user using the MySQL Command Line // Log on to MySQL@> Mysql-u root-P@> Password// Create a userMysql> insert into mysql. User (host, user, password) values ('localhost',

MySQL can assign strict and complex permissions to different users. Most of these operations can be implemented using the SQL command grant (assign permission) and revoke (revoke permission. Grant can assign the specified permission to a specific

Group_concat usage The rules are as follows: Group_concat ([distinct] expr [, expr...][Order by {unsigned_integer | col_name | expr}[ASC | DESC] [, col_name...][Separator str_val])Problems with group_concatIf the column to be merged is of the int

You have to specify 0 (meaning false) or 1 (meaning true) as the default. Here is an example: Create Table mytable ( Mybool Boolean not null default 0); FYI: Boolean is an alias for tinyint (1 ). Mysql> Create Table mytable (-> Mybool Boolean not

MySQL does not allow you to run select while updating a table The work und is to generate a temporary table from a derived table. In this way, both update and select Update tb_trade_1 inner join (select tid, count (*) as CNT from tb_order_1 group

How to install MySQL using Yum: Yum install mysql-Server Because yum is accidentally deleted. Therefore, it is forced to install the SDK using commands. The latest MySQL versions require cmake compilation and installation. It is estimated that this

MySQL obtains the value of the auto_increment field just inserted. Select max (ID) from testnotnull cannot be used; In this way, you can obtain the value of the incremental field you just inserted, Multithreading is not considered.   A better method

1. Enter the specified schema database (storing the information of other databases) Use information_schema 2. query the size of all data Select Concat (round (sum (data_length/1024/1024), 2), 'mb') as data from tables 3. view the size of the

1. MySQL Http://www.xiazaiba.com/html/361.html 2. Install MySQL Http://www.jz123.cn/text/2719438.html Note that the first installation requires you to set the root password. Convert c: \ Program Files \ mysql server 5.5 \ bin Add it to the

Today, we need to merge 30 MySQL tables for analysis. Each table has the same structure, with a data volume of about 2 million. The data table is in MyISAM format, and the data file size is about 800 mb. When I use insert into... select to merge

MySQL has a function to log down and run slow SQL statements. This log is not available by default. To enable this function, modify my. CNF or add some parameters when MySQL is started. If you modify it in my. CNF, add the following