创建序列在mysql中怎么写

CREATE TABLE sequence_table (
    seq_name VARCHAR(50) NOT NULL,
    current_val INT NOT NULL,
    increment INT NOT NULL DEFAULT 1,
    PRIMARY KEY (seq_name)
);

INSERT INTO sequence_table (seq_name, current_val, increment) VALUES ('my_sequence', 0, 1);

DELIMITER //

CREATE PROCEDURE nextval (IN seq_name VARCHAR(50), OUT next_val INT)
BEGIN
    UPDATE sequence_table
    SET current_val = current_val + increment
    WHERE seq_name = seq_name;

    SELECT current_val INTO next_val
    FROM sequence_table
    WHERE seq_name = seq_name;
END //

DELIMITER ;

CALL nextval('my_sequence', @next_val);
SELECT @next_val;