mysql创建序列

############### mysql 创建序列 ##############

CREATE TABLE IF NOT EXISTS `sequence` (

`name` varchar(50) NOT NULL,

`current_value` int(11) NOT NULL,

`increment` int(11) NOT NULL DEFAULT '1'

) ENGINE=MyISAM DEFAULT CHARSET=utf8 CHECKSUM=1 DELAY_KEY_WRITE=1 ROW_FORMAT=DYNAMIC COMMENT='序列表，命名seq_[table_name]';

DROP FUNCTION IF EXISTS `currval`;

DELIMITER //

CREATE FUNCTION `currval`(seq_name VARCHAR(50)) RETURNS int(11)

READS SQL DATA

DETERMINISTIC

BEGIN

DECLARE VALUE INTEGER;

SET VALUE = 0;

SELECT current_value INTO VALUE FROM sequence WHERE NAME = seq_name;

RETURN VALUE;

END//

DELIMITER ;

DROP FUNCTION IF EXISTS `nextval`;

DELIMITER //

CREATE FUNCTION `nextval`(seq_name VARCHAR(50)) RETURNS int(11)

DETERMINISTIC

BEGIN

UPDATE sequence SET current_value = current_value + increment WHERE NAME = seq_name;

RETURN currval(seq_name);

END//

DELIMITER ;

INSERT INTO `sequence` (`name`, `current_value`, `increment`) VALUES
('seq_appMonitorResult', 0, 1);

select nextval("seq_appMonitorResult");

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