下面是实现序列化的代码
先建一个序列表,如下:
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s_[table_name]’;
INSERT INTO `sequence` (`name`, `current_value`, `increment`) VALUES
(’s_blog_account’, 0, 1)
DROP FUNCTION IF EXISTS `curial`;
DELIMITER //
CREATE FUNCTION `curial`(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 ;
没有错误之后就;可以使用了.
如想要实现 id 序列,输入
alter table tb_user modify id integer auto_increment;
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