MySQL

Preparation package: Httpd-2.2.6.tar.gz mysql-5.0.41.tar.gz php-5.2.6.tar.gz libxml2-2.6.30.tar.gz before installation is best to shut down the firewall, wait for the environment after installation and then unified configuration firewall (Service

MySQL Study Notes (iii) Performance Optimization 11. MySQL database Locking Mechanism MySQL database locks include table-level locks, row-level locks, and page-level locks. There are four main differences between the InnoDB Storage engine and the

  Solve the problem of slow MySQL LoginSymptom:The system is normal and the local login speed is fast. There is no problem with the query and other operations. No error message is reported in the log. However, remote login is abnormal and slow, and

Show index from tablename · TableTable name.· Non_uniqueIf the index cannot contain duplicate words, the value is 0. If yes, it is 1.· Key_nameThe name of the index.· Seq_in_indexThe column serial number in the index, starting from 1.·

Recently, I found that an error "error making query: MySQL server has gone away" always occurs after a previous project is run. In fact, the project is very simple. One is the socket server, and the other is the Socket Client. The client sends a

Preface This blog post was previously written and is not very professional in some places. Let's take a look at it. Of course, it is not a problem to install MySQL by following the steps. Installation environment description: System: Ubuntu

This was changed based on the previous example ~~~ Note: The system. data. the DLL is unity, editor, Data, Mono, Lib, Mono, 2.0, and system. data. DLL, but MySQL. data. I don't know how to judge the dll version. I used 1.0.6.15336 but always

1. Export the entireDatabase Mysqldump-u username-P Database Name> exported file name Mysqldump-u wcnc-P smgp_rj_wcnc> wcnc. SQL 2. Export a table Mysqldump-u user name-P database name Table Name> exported file name Mysqldump-u wcnc-P smgp_

Replication thread MySQL replication is an asynchronous replication process, from one MySQL instace (we call it the master) to another MySQL instance (we call it the slave ). The entire replication process between the master and slave is mainly

1. Assume that your table contains columns A, B, and C and you want to import the data to the table in your database. The corresponding fields are col1, col2, and col3. 2. Add a column to your table and use the Excel Formula to automatically

The requirement is as follows (a problem on csdn): There is a table in MySQL: article (field: ID, type, date), type has 1-10, 10 types. Now we need to use SQL to find a collection of the First n data of the latest time in each type.   There

Hibernate MySQL ing type hibernate MySQL ing type 1. hibernate ing type hibernate MySQL ing type Hibernate ing type Java type Standard SQL type Size and value range Integer or int Int or Java. Lang. Integer

I recently worked on a project in my company to build a system. I used C # development,. NET Framework at the front end, and MySQL database at the back end. I used SQL Server for my website, so I don't know much about MySQL, so I don't understand

MySQL Study Notes (6) scalability design-memcached1. as a tool for improving system performance The following figure shows a brief diagram of using memchched as the cache service layer: It can be seen that all data needs to be inserted,

MySQL Study Notes (1) Basic Introduction 1. Comparison with other databases 1.1 Function Comparison MySQL basically implements most of the ansi SQL 92 standards, and only a small part is not frequently used. In terms of transaction support, although

Yesterday I wrote a program connected to MySQL. The compiling result indicates that mysql. h cannot be found, and I am depressed. How can I not find it? So I could not find it manually, so I used find to find it. then google found that many netizens

I always thought that MySQL would randomly query several pieces of data. Select * From 'table' order by rand () limit 5You can.However, the test results show that the efficiency is very low. It takes more than 8 seconds to query 5 data records in a

Initial installation method:   1. Download MySQL 5.0 from the official website. 2. Modify the firewall settings and add a new port to allow exceptions. The port name is MySQL and the opened port is TCP 3306. In this case, you should click

1. Connect to MySQL Format: mysql-H host address-u user name-P User Password Ii. Change the password Format: mysqladmin-u username-P old Password New Password   3. Add new users. (Note: Unlike the above, the following commands in the MySQL

1. IndexingIn addition to the ordered search mentioned above, the database can greatly improve the query efficiency by using various fast locating technologies. In particular, when the data volume is very large and the query involves multiple tables,