学习mysql的一些记录_MySQL
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SHOW VARIABLES;/**查看服务器实际运行参数值**/
02 /*查询是否存在 此存储过程。如果存在则删除*/
03 DROP PROCEDURE IF EXISTS helloword
04 /*测试存储过程*/
05 DELIMITER //
06 CREATE PROCEDURE helloword()
07 BEGIN
08 SELECT 'hellor word';
09 END
10 /*调用存储过程*/
11 CALL helloword
12
13 DROP PROCEDURE IF EXISTS pr_add
14 /*测试在存储过程中选择语句*/
15 DELIMITER //
16 CREATE PROCEDURE pr_add(
17 a INT,
18 b INT)
19 BEGIN
20 IF a IS NULL THEN
21 SET a=0;
22 END IF;
23 SELECT a+b;
24 END
25 /*调用*/
26 CALL pr_add(NULL,1);
27 /*删除存储过程*/
28 DROP PROCEDURE pr_add;
29 /*创建视图*/
30 CREATE VIEW teabc AS SELECT * FROM abcd WHERE abc='aa'
31 SELECT * FROM teabc
32 /*查询用户名权限*/
33 SHOW GRANTS FOR root@localhost
34 /*创建视图 触发器支持事件 insert update delete*/
35 /*此含义:如果abcd这张表插入记录时 运行begin内语句SetUserHome 为触发品名称*/
36 DELIMITER //
37 CREATE TRIGGER SetUserHome BEFORE INSERT ON abcd
38 FOR EACH ROW
39 BEGIN
40 INSERT INTO stime VALUE(NOW(),'hello word');
41 END
42
43 /*操作用户相关*/
44 /*权限:select,insert,update,delete,create,drop,index,alter,grant,references,reload,shutdown,process,file
45 如果允许全部权限,可以用all或者all privileges代替以上权限。*/
46 /*alter 修改表和索引create 创建数据库和表delete 删除表中已有的记录drop 抛弃(删除)数据库和表index 创建或抛弃索引
47 insert 向表中插入新行reference 未用select 检索表中的记录update 修改现存表记录file 读或写服务器上的文件
48 process 查看服务器中执行的线程信息或杀死线程reload 重载授权表或清空日志、主机缓存或表缓存。shutdown 关闭服务器
49 all 所有;all privileges同义词usage 特殊的“无权限”权限*/
50 /*修改用户密码 需要重启服务*/
51 UPDATE USER SET PASSWORD=PASSWORD('zhouhui') WHERE USER='root';
52 /*创建用户 大意:可以操作test数据库的所有表 mfkwfc只能由127.0.0.1登录 密码是123*/
53 GRANT ALL PRIVILEGES ON test.* TO mfkwfc@127.0.0.1 IDENTIFIED BY '123';
54 /*取消用户此权力*/
55 REVOKE INSERT ON test.* FROM mfkwfc@127.0.0.1;
56 /*添加用户此权力*/
57 GRANT INSERT ON test.* TO mfkwfc@127.0.0.1
58 /*修改密码 USAGE无权限的意思*/
59 GRANT USAGE ON test.* TO mfkwfc@127.0.0.1 IDENTIFIED BY 'mfkwfc';
60 /*刷新权限*/
61 FLUSH PRIVILEGES;
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