mysql数据库---编码格式基本操作
1.查看数据库编码格式
mysql> show variables like 'character_set_database';
2.查看数据表的编码格式
mysql> show create table <tableName>;
3.创建数据库时指定数据库的字符集
mysql>create database <databaseName> character set utf8;
4.创建数据表时指定数据表的编码格式
create table tb_books ( name varchar(128) not null, price double not null, bookCount int not null, author varchar(128) not null ) default charset = utf8;
5.修改数据库的编码格式
mysql>alter database <databaseName> character set utf8;
6.修改数据表格编码格式
mysql>alter table <tableName> character set utf8;
7.修改字段编码格式
mysql>alter table <tableName> change <column_name> <column_name> <type> character set utf8; mysql>alter table user change username username varchar(128) character set utf8 not null;
8.添加外键
mysql>alter table tb_product add constraint fk_1 foreign key(factoryid) references tb_factory(factoryid); mysql>alter table <tableName> add constraint <F_keyName> foreign key<column_name> REFERENCES <F_tableName><column_name>;
9.删除外键
mysql>alter table tb_people drop foreign key fk_1; mysql>alter table <tableName> drop foreign key <F_keyName>;
努力成为一个有情怀的程序员~