MySQL inserts millions of data (using functions and stored procedures)

Case study ： Using stored procedures to mysql Insert millions of data .

One 、 Create two new tables ：dept,emp surface ：

1、 establish dept surface ：

CREATE TABLE `dept` (
  `id` int unsigned NOT NULL AUTO_INCREMENT,
  `deptno` mediumint unsigned NOT NULL DEFAULT '0',
  `dname` varchar(20) NOT NULL DEFAULT '',
  `loc` varchar(20) NOT NULL DEFAULT '',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=gbk;

2、 establish emp surface ：

CREATE TABLE `emp` (
  `id` int unsigned NOT NULL AUTO_INCREMENT,
  `empno` mediumint unsigned NOT NULL DEFAULT '0',
  `empname` varchar(20) NOT NULL DEFAULT '',
  `job` varchar(20) NOT NULL DEFAULT '',
  `sal` decimal(7,2) DEFAULT NULL,
  `deptno` int DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=500001 DEFAULT CHARSET=gbk;

Two 、 Establish functions and stored procedures , The following functions need to be established ：

1、 establish rand_str（） function . This function generates a random string ：

CREATE DEFINER=`root`@`%` FUNCTION `rand_str`(n int) RETURNS varchar(255) CHARSET utf8mb4
BEGIN
	DECLARE
	chars_str VARCHAR ( 100 ) DEFAULT 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
DECLARE
	returns_str VARCHAR ( 255 ) DEFAULT '';
DECLARE
	i INT DEFAULT 0;
WHILE
	i < n DO
	
	SET returns_str = CONCAT(returns_str,SUBSTRING( chars_str, FLOOR( 1+ RAND( ) * 52 ) , 1));

SET i = i + 1;

END WHILE;
	RETURN returns_str;
END

 2、 Establish random number function ：rand_num():

CREATE DEFINER=`root`@`%` FUNCTION `rand_num`( ) RETURNS int
BEGIN
DECLARE
	i INT DEFAULT 0;

SET i = FLOOR( 100+ RAND( ) * 10 );
RETURN i;

END

 3、 Create stored procedures ：insert_dept: Insert dept Table stored procedures ：

CREATE DEFINER=`root`@`%` 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 ( deptno, dname,loc )VALUES((START + i), rand_str(10),rand_str(6));
	UNTIL i = max_num
END REPEAT;
COMMIT; END

4、 Create stored procedures insert_tmp: Insert emp Table stored procedures ：

CREATE DEFINER=`root`@`%` PROCEDURE `insert_tmp`( 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 ( empno, empname,sal,deptno )VALUES((START + i), rand_str(6),100,rand_num());
	UNTIL i = max_num
END REPEAT;
COMMIT; END

3、 ... and ： To test ：

1、 Test insertion first dept：

CALL insert_dept(1, 10);

give the result as follows ：

From that , Was successfully inserted .

Then we are right emp Insert millions of data , See how long it takes .

CALL insert_tmp(1000000, 5000000)

The result is ：

  From this we can see that , Insert 50W Data need 4 About minutes . It feels quite slow