mysql null not working

MySQL links, viewing databases, working with databases, viewing tablesMysql> Show databases;+--------------------+| Database |+--------------------+| Information_schema | | MySQL | | Performance_schema | | QQ | | Test |+--------------------+5 rows

Working with databasesView Database It is often useful to get a list of databases on a server. Execute show databases; the command will be done. mysql> show databases; Create a database mysql> CREATE DATABASE Db_test;Query

MySQL常用指令，java，php程序员，数据库工程师必备。程序员小冰常用资料整理MySQL common commands (for reference)The most common display commands are:1. Display the list of databases.show databases;2. Display the data table in the library:Use MySQL;Show tables;3, display the

MySQL builds a series of multiple instances. The so-called multi-instance is to build and run multiple MySQL instances on one server. each instance uses different service ports and listens through different sockets. physically, each instance has an

MySQL builds a series of multiple instances. The so-called multi-instance is to build and run multiple MySQL instances on one server. Each instance uses different service ports and listens through different sockets. Physically, each instance has an

The so-called multi-instance is to build and run multiple MySQL instances on a server. Each instance uses different service ports and listens through different sockets. Physically, each instance has an independent parameter configuration file and

Concrete Example 1. PHP Server ComponentsFor beginners, it is recommended to use the integrated server component, which already includes PHP, Apache, Mysql and other services, eliminating the time spent by developers in the tedious configuration

mysql| Data | Database summary In this chapter, we will focus on how to work with the MySQL database using Structured Query Language (SQL). (2002-08-29-14:11:10) -------------------------------------------------------------------------------- By

  [Content Overview] This book is designed and implemented by a MySQL expert from Sun's Chinese Engineering Institute. The author divides the complex MySQL kernel into multiple functional subsystems to resolve various difficulties in understanding

Overview replication is usually used to create a copy of the master node to ensure high availability by adding redundant nodes. Of course, replication can also be used for other purposes, such as reading and analyzing data on the slave node. In