mysql add field

In the reconstruction of the site, the data structure is usually modified, so add, delete, add the MySQL table field is unavoidable, and sometimes for convenience, but also increase the modification of the table or field comments, the same field

I. Commonly Used MySQL command line commands1. Start the MySQL service. Net start MySQL Stop MySQL service. net stop MySQL 2. netstat-Na | findstr 3306: Check the listening port. findstr is used to check whether the following port exists. 3. log on

In the reconstruction of the site, the data structure is usually modified, so add, delete, add the MySQL table field is unavoidable, and sometimes for convenience, but also increase the modification of the table or field comments, the same field

Mysql changes the table structure: add, delete, modify, and adjust the field order to add a field: altertable 'user _ movement_log 'AddcolumnGatewayIdintnotnulldefault0AFTER 'regionid' (after which field is added) Delete the field: altertable 'user _

1. Display the list of databasesshow databases; # View all current databasesShow Databases \g #以行的方式显示2. On the command line, execute the SQL statementMysql-e ' show databases '-uroot-p123456mysqlshow-uroot-p123456 # not used, just remember the one

How should MySQL add fields be implemented? This is a lot of new contacts MySQL database has been mentioned, the following is to introduce you to MySQL add fields and delete the field method, I hope you can be enlightened.MySQL add field:

Mysql changes the table structure: add, delete, modify, and adjust the field order to add a field: altertable 'user _ movement_log 'AddcolumnGatewayIdintnotnulldefault0AFTER 'regionid' (after which field is added) Delete the field: altertable 'user _

1. Add a field ALTER TABLE user add COLUMN new1 VARCHAR (x) DEFAULT NULL; 　　 Add a field that defaults to null ALTER TABLE user add COLUMN new2 VARCHAR (a) not NULL; 　　　　　　　　　　　　　　 Add a field, default cannot be empty//2. Delete a field ALTER TABLE

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 add field: ALTER TABLE ' User_movement_log ' add column Gatewayid int not null default 0 after ' RegionID ' (added after which field) To delete a field: ALTER TABLE ' user_movement_log ' drop column Gatewayid To