时间:2021-07-01 10:21:17 帮助过:18人阅读
创建表DEPT
代码如下:
CREATE TABLE dept( /*部门表*/
deptno MEDIUMINT UNSIGNED NOT NULL DEFAULT 0,
dname VARCHAR(20) NOT NULL DEFAULT "",
loc VARCHAR(13) NOT NULL DEFAULT ""
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ;
代码如下:
CREATE TABLE emp
(empno MEDIUMINT UNSIGNED NOT NULL DEFAULT 0,
ename VARCHAR(20) NOT NULL DEFAULT "",
job VARCHAR(9) NOT NULL DEFAULT "",
mgr MEDIUMINT UNSIGNED NOT NULL DEFAULT 0,
hiredate DATE NOT NULL,
sal DECIMAL(7,2) NOT NULL,
comm DECIMAL(7,2) NOT NULL,
deptno MEDIUMINT UNSIGNED NOT NULL DEFAULT 0
)ENGINE=MyISAM DEFAULT CHARSET=utf8 ;
工资级别表
代码如下:
CREATE TABLE salgrade
(
grade MEDIUMINT UNSIGNED NOT NULL DEFAULT 0,
losal DECIMAL(17,2) NOT NULL,
hisal DECIMAL(17,2) NOT NULL
)ENGINE=MyISAM DEFAULT CHARSET=utf8;
INSERT INTO salgrade VALUES (1,700,1200);
INSERT INTO salgrade VALUES (2,1201,1400);
INSERT INTO salgrade VALUES (3,1401,2000);
INSERT INTO salgrade VALUES (4,2001,3000);
INSERT INTO salgrade VALUES (5,3001,9999);
随机产生字符串
定义一个新的命令结束符合
代码如下:
delimiter $$
代码如下:
drop function rand_string $$
代码如下:
create function rand_string(n INT)
returns varchar(255)
begin
declare chars_str varchar(100) default
'abcdefghijklmnopqrstuvwxyzABCDEFJHIJKLMNOPQRSTUVWXYZ';
declare return_str varchar(255) default '';
declare i int default 0;
while i < n do
set return_str =concat(return_str,substring(chars_str,floor(1+rand()*52),1));
set i = i + 1;
end while;
return return_str;
end $$
delimiter ;
select rand_string(6);
代码如下:
delimiter $$
drop function rand_num $$
代码如下:
create function rand_num( )
returns int(5)
begin
declare i int default 0;
set i = floor(10+rand()*500);
return i;
end $$
delimiter ;
select rand_num();
向emp表中插入记录(海量的数据)
代码如下:
delimiter $$
drop procedure insert_emp $$
create procedure insert_emp(in start int(10),in max_num int(10))
begin
declare i int default 0;
set autocommit = 0;
repeat
set i = i + 1;
insert into emp values ((start+i) ,rand_string(6),'SALESMAN',0001,curdate(),2000,400,rand_num());
until i = max_num
end repeat;
commit;
end $$
delimiter ;
调用刚刚写好的函数, 1800000条记录,从100001号开始
代码如下:
call insert_emp(100001,1800000);
向dept表中插入记录
代码如下:
delimiter $$
drop procedure insert_dept $$
create procedure insert_dept(in start int(10),in max_num int(10))
begin
declare i int default 0;
set autocommit = 0;
repeat
set i = i + 1;
insert into dept values ((start+i) ,rand_string(10),rand_string(8));
until i = max_num
end repeat;
commit;
end $$
delimiter ;
call insert_dept(100,10);
向salgrade 表插入数据
代码如下:
delimiter $$
drop procedure insert_salgrade $$
create procedure insert_salgrade(in start int(10),in max_num int(10))
begin
declare i int default 0;
set autocommit = 0;
ALTER TABLE emp DISABLE KEYS;
repeat
set i = i + 1;
insert into salgrade values ((start+i) ,(start+i),(start+i));
until i = max_num
end repeat;
commit;
end $$
delimiter ;
#测试不需要了
#call insert_salgrade(10000,1000000);
希望本文所述对大家的MySQL数据库程序设计有所帮助。