CREATE TABLE filler (
        id INT NOT NULL PRIMARY KEY AUTO_INCREMENT
) ENGINE=Memory;

CREATE TABLE t_column (
        id INT NOT NULL PRIMARY KEY,
        col1 VARCHAR(10),
        col2 VARCHAR(10),
        col3 VARCHAR(10),
        col4 VARCHAR(10),
        col5 VARCHAR(10),
        col6 VARCHAR(10),
        col7 VARCHAR(10),
        col8 VARCHAR(10),
        col9 VARCHAR(10),
        col10 VARCHAR(10),
        col11 VARCHAR(10),
        col12 VARCHAR(10),
        col13 VARCHAR(10),
        col14 VARCHAR(10),
        col15 VARCHAR(10),
        col16 VARCHAR(10),
        col17 VARCHAR(10),
        col18 VARCHAR(10),
        col19 VARCHAR(10),
        col20 VARCHAR(10)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

DELIMITER $$

CREATE PROCEDURE prc_filler(cnt INT)
BEGIN
        DECLARE _cnt INT;
        SET _cnt = 1;
        WHILE _cnt <= cnt DO
                INSERT
                INTO    filler
                SELECT  _cnt;
                SET _cnt = _cnt + 1;
        END WHILE;
END
$$

DELIMITER ;

START TRANSACTION;
CALL prc_filler(1000000);
COMMIT;

INSERT
INTO    t_column
SELECT  id,
        LPAD('', RAND(20090521) * 10, 'a'), 
        LPAD('', RAND(20090521 << 1) * 10, 'a'), 
        LPAD('', RAND(20090521 << 2) * 10, 'a'), 
        LPAD('', RAND(20090521 << 3) * 10, 'a'), 
        LPAD('', RAND(20090521 << 4) * 10, 'a'), 
        LPAD('', RAND(20090521 << 5) * 10, 'a'), 
        LPAD('', RAND(20090521 << 6) * 10, 'a'), 
        LPAD('', RAND(20090521 << 7) * 10, 'a'), 
        LPAD('', RAND(20090521 << 8) * 10, 'a'), 
        LPAD('', RAND(20090521 << 9) * 10, 'a'), 
        LPAD('', RAND(20090521 << 10) * 10, 'a'), 
        LPAD('', RAND(20090521 << 11) * 10, 'a'), 
        LPAD('', RAND(20090521 << 12) * 10, 'a'), 
        LPAD('', RAND(20090521 << 13) * 10, 'a'), 
        LPAD('', RAND(20090521 << 14) * 10, 'a'), 
        LPAD('', RAND(20090521 << 15) * 10, 'a'), 
        LPAD('', RAND(20090521 << 16) * 10, 'a'), 
        LPAD('', RAND(20090521 << 17) * 10, 'a'), 
        LPAD('', RAND(20090521 << 18) * 10, 'a'), 
        LPAD('', RAND(20090521 << 19) * 10, 'a')
FROM    filler;