MySQL

MySQL PRIMARY key operationTo delete a table primary key:ALTER TABLE student drop PRIMARY key;Add Table primary key:ALTER TABLE student Add primary key (ID);Reset the primary key increment (if you need to perform a delete table primary KEY statement

1. Check the my.cnf to see if there is a password ... That's one of those, isn't it?2. If you can restart,First use the –skip-grant-tables parameter restart, and then change the password, and then remove the –skip-grant-tables parameter restart, pay

1. Check the compilation parameters of PHP/usr/local/php/bin/php-config--configure-optionsOr/usr/local/php/bin/php-r "Phpinfo ();" | Grep-i ConfigureOr/usr/local/php/bin/php-i | grep Configure2. View MySQL compilation

First, mathematical functionsABS (x) returns the absolute value of XBIN (x) returns the binary of X (Oct returns octal, HEX returns hex)CEILING (x) returns the smallest integer value greater than XEXP (x) return value E (base of natural logarithm) x

Many friends have just started to contact MySQL database server, the following is a user compiled a MySQL installation tutorial, step details also have detailed description.MySQL5.0 version of the installation illustrated tutorial is for beginners

in standard SQL, a query this includes a GROUP BY clause cannot refer to nonaggregated columns in the select list that AR E not named in the GROUP BY clause. For example, this query was illegal in standard SQL because the name column in the select

Reference: http://www.2cto.com/database/201406/309521.htmljust install the xampp and use localhost to run properly.Phpmyadimin can also log in normallyWhy you can enter mysql-uroot-p123 on the command linebut I can't.Clearly in front of, why show

Getting Started with SQLIt is necessary to be proficient in writing SQL before you are ready to become a MySQL DBA. Equivalent conversions between exists and joins, basic row-and-column conversions, and the mastery of SQL loops can be very helpful

Linux to turn on MySQL remote connection setup steps.MySQL remote connection linuxserviceserverusermysql default root user only local access, cannot remotely connect to manage MySQL database, Linux how to turn on MySQL remote connection? The setup

Reprint: Original AddressFirst, backup common Operation Basic command 1, backup command mysqldump formatFormat:mysqldump -h主机名 -P端口 -u用户名 -p密码 –database 数据库名 > 文件名.sql2. Backup MySQL database as a format with delete tableBacking up the MySQL

After installing MySQL, use the command login MySQL unexpectedly error, mysql error 1045 (28000): Access denied for user ' root ' @ ' localhost ' (using Password:yse), This error is very depressed, after careful analysis, know that the error and

When installing MySQL:Error phenomena:[[email protected] opt]# rpm-ivh mysql-server-5.5.32-1.el6.x86_64.rpm Preparing ... ################## ######################### [100%]file/usr/share/mysql/charsets/index.xml from Install of mysql-server-5.5.32-1

Mysql query in action query results display the _mysql_ script house in the In collection orderMySQL Query in operation, the query results are displayed in the order of in collection Copy CodeThe code is as follows:SELECT * from test where ID in (3

In our development of the efficiency has always been a problem, especially for a lot of large data volume operation, today we ran into a random query data, at first we might think of the simplest order by RAND () to operate but the efficiency is not

1. Add header file path (include path in MySQL installation path)2. Add library files (copy libmysql.lib directly from the MySQL installation path)3. Programming Operation DatabaseCodeAccessToMySQL.cpp: Defines the entry point of the console

The event scheduler in MySQL can periodically increase, delete, and execute operations on the database, which is equivalent to temporary triggers in the database, as with the execution plan tasks in the Linux system, which can greatly reduce the

InnoDB is a multi-threaded concurrent storage engine, the internal read and write are implemented with multithreading, so innodb internal implementation of a relatively efficient concurrency synchronization mechanism. InnoDB does not directly use

MySQL Slow Log on the company line, has not been well monitored. While I was idle last week, I wrote the monitoring script, and today I specially sent out the code to share with 51 Bo friends.For the annotations and the overall idea of the script, I'

Hive Debug Information Display mode:./hive-hiveconf Hive.root.logger=debug,consoleVery useful.By default, the hive metadata is saved in the embedded Derby database, allowing only one session connection and only for simple testing. In order to

Open the network of frequently visited novels in the morning http://www.xiaoxiaoshuwu.com/ , Ben wanted to see if the novel was updated. But 650) this.width=650; "src=" Http://img.baidu.com/hi/jx2/j_0021.gif "alt=" J_0021.gif "/>650) this.width=650;