mysql insert null

1. Full backup and incremental backup 1.1 full-scale backupFull-volume data is all the data in the database, and a full backup is the backup of all the data in the database.Back Up all libraries:mysqldump -uroot -p123456 -S /data/3306/mysql.sock -F -

In MySQL, the processing of NULL fields, it is important to note that when there is null in the processing query condition, it is possible that the value you get is not desired because, in MySQL, the null value equals (=) is judged equal (=) or

This article is a MySQL database insert, UPDATE, delete and replace statements in the use of detailed analysis of the introduction, the need for friends to refer to the MySQL database insert and UPDATE statements Introduction: The SQL used to

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

We often see MySQL NULL strings and NULL values, but they are not a concept. The following describes the differences between NULL and MySQL NULL strings for your reference. For SQL beginners, the concept of NULL value is often confusing. They often

A brief introduction to 1.1 MongoDBIn today's database market, MySQL is undoubtedly a place to occupy. As an open-source relational database , MySQL is widely used in the background of major web sites, and assumes the important role of information

Explicit_defaults_for_timestampMySQL5.6 Version IntroductionExplicit_defaults_for_timestampto control the timestamp NULL handling of Values timestamp not NULL insert null value, no error, no warning if the my.cnf Zhong

MySQL Optimization-Delete Insert update and mysql optimization insert update Reprinted please indicate the source: http://blog.csdn.net/l1028386804/article/details/46581769 Insert Insert multi-row query results into the table Syntax INSERT INTO

1. download MySql 1. download MySql Open http://www.mysql.com/downloads/mysql/#downloads download in browser My downloaded version is Red Hat 5 version of http://www.mysql.com/downloads/mirror.php? Id = 407552 Upload the file to the server, or

Differences between null and not null in mysql and efficiency issues Mysql users may encounter the following situations: 1. My field type is not null. Why can I insert null values? 2. Why is not null more efficient than null? 3. When determining