Question

I have a table with ONE bigint-field. Now I would like to insert millions of rows with an increment so I came up with this procedure:

CREATE PROCEDURE insertMe()
BEGIN
 DECLARE i BIGINT DEFAULT 1;
 WHILE (i <= 999999999) DO  
   INSERT INTO mytable values(i);  
   SET i=i+1;
 END WHILE;
END;

Of course this beast takes way too long, so normally I would do the following:

INSERT INTO mytable values(1),(2),(3) etc

But how do I create the String then and wouldn’t that take too long as well?

Answer 1

You can use an AUTO_INCREMENT field. If you attempt to insert a NULL in that field, MySQL generates the auto number for you so there is no need to build the (1), (2), … string. Give this a try:

CREATE TABLE seed(column1 BIGINT AUTO_INCREMENT PRIMARY KEY) ENGINE=MyISAM;

-- INSERT ONE ROW TO BEGIN WITH
INSERT INTO seed(column1) VALUES(NULL);

-- RUN THIS QUERY 20 TIMES TO GENERATE 1,048,576 ROWS
INSERT INTO seed(column1)
SELECT NULL
FROM seed;

20 iterations of the above queries on a MyISAM table took ~4.5 seconds.