Mysql快速插入千万条数据的实战教程(2)-木庄网络博客

四.创建函数

1.随机产生字符串

DELIMITER $
CREATE FUNCTION RAND_STR(n INT) RETURNS VARCHAR(255)
BEGIN
 DECLARE chars_str VARCHAR(100) DEFAULT 'abcdefghijklmnopqrstuvwsyzABCDEFGHIJKLMNOPQRSTUVWXYZ'; 
	 DECLARE return_str VARCHAR(255) DEFAULT '';
 DECLARE i INT DEFAULT 0;
	 WHILE i< n DO 
	 SET return_str =COUCAT(return_str,SUBSTRING(chars_str,FLOOR(1+RAND()*52),1));
	 SET i= i+1;
 END WHILE;
	 RETURN return_str;
END $

2.随机产生部门编号

DELIMITER $
CREATE FUNCTION RAND_num() RETURNS INT(5)
BEGIN
 DECLARE i INT DEFAULT 0; 
	 SET i= FLOOR(100+RAND()*10);
	 RETURN i;
END $

五.创建存储过程

1. emp表存储过程

DELIMITER $
CREATE PROCEDURE insert_emp(IN START INT(10),IN max_num INT(10))
BEGIN
  DECLARE i INT DEFAULT 0;
		SET autocommit = 0;
		REPEAT #重复
		SET i = i + 1;
		INSERT INTO emp(empon,ename,job,mgr,hiredate,sal,comm,depton) VALUES ((START+i),RAND_STR(6),'SALESMAN',0001,CURDATE(),2000,400,RAND_num());
	 UNTIL i = max_num
 END REPEAT;
	 COMMIT;
END $

2.dept表存储过程

DELIMITER $
CREATE PROCEDURE insert_dept(IN START INT(10),IN max_num INT(10))
BEGIN
  DECLARE i INT DEFAULT 0;
		SET autocommit = 0;
		REPEAT #重复
		SET i = i + 1;
		INSERT INTO dept(deptno,dname,loc) VALUES ((START+i),RAND_STR(10),RAND_STR(8));
	 UNTIL i = max_num
 END REPEAT;
	 COMMIT;
END $