mysql DCL數據控制語言
-- 維護性操作 都是在cmd下操作的
連接數據庫：
本機：mysql [-h localhost] -u account -p
遠程：mysql [-h remote_ip] -u account -p
顯示當前所有數據庫：show databases;
切換數據庫：use db_name;
顯示當前數據庫下的表：show tables;
授權遠程訪問：
grant privileges on 數據庫.* to [email protected] identified by password(pwd_string);
是授權生效：
重啟mysql服務
flush privileges;
privileges:
SELECT,INSERT,...
更新權限 flush privileges 或者 重啟mysql set start mysql
退出 mysql：exit
收回訪問權限：
revoke privileges on 數據庫.* from [email protected];
-- 用戶管理：
-- 新建用戶
create user user_name identified by ‘password_value‘;
-- 修改用戶
rename user user_name to new_user_name;
set password for user_name = password(‘new_password‘);
-- 刪除用戶
drop user user_name[,user_name2,...];
-- 查看用戶
select user,host from mysql.user;
-- 查看在線用戶
SELECT SUBSTRING_INDEX(host, ‘:‘, 1) AS host_short,
GROUP_CONCAT(DISTINCT user) AS users,
COUNT(*) AS threads
FROM information_schema.processlist
GROUP BY host_short
ORDER BY COUNT(*), host_short;
-- 創建數據庫
create database db_name [default character set utf8 collate utf8_general_ci];
實例：create database school default character set utf8 collate utf8_general_ci;
-- 刪除數據庫
drop database db_name;
實例：drop database school;
-- 備份數據庫
mysqldump -u user_name -p db_name > backupfile
mysqldump -u user_name -p db_name [table_name]> backupfile
實例：mysqldump - u root -p employees > employees.sql
-- 還原數據庫
mysql -u root -p
確定要還原的數據庫是否存在，不存在則創建
切換到要還原的數據庫上
執行還原操作：source backup.sql
實例：1.mysql -u root -p
2.show databases
3.creat databases employees default character set utf8
4.user employees
5.source employees.sql
-- 程序設計
mysql DCL數據控制語言