-- 序列表
DROP TABLE IF EXISTS sequence;
CREATE TABLE sequence (
name VARCHAR(50) NOT NULL,
current_value INT NOT NULL,
increment INT NOT NULL DEFAULT 1,
PRIMARY KEY (name)
) ENGINE=InnoDB;
-- INSERT INTO sequence VALUES ('MovieSeq',3,5);
-- 获取当前值
DROP FUNCTION IF EXISTS currval;
DELIMITER $
CREATE FUNCTION currval (seq_name VARCHAR(50))
RETURNS INTEGER
CONTAINS SQL
BEGIN
DECLARE value INTEGER;
SET value = 0;
SELECT current_value INTO value
FROM sequence
WHERE name = seq_name;
RETURN value;
END$
DELIMITER ;
-- 获取下一个值
DROP FUNCTION IF EXISTS nextval;
DELIMITER $
CREATE FUNCTION nextval (seq_name VARCHAR(50))
RETURNS INTEGER
CONTAINS SQL
BEGIN
UPDATE sequence
SET current_value = current_value + increment
WHERE name = seq_name;
RETURN currval(seq_name);
END$
DELIMITER ;
-- 设置值
DROP FUNCTION IF EXISTS setval;
DELIMITER $
CREATE FUNCTION setval (seq_name VARCHAR(50), value INTEGER)
RETURNS INTEGER
CONTAINS SQL
BEGIN
UPDATE sequence
SET current_value = value
WHERE name = seq_name;
RETURN currval(seq_name);
END$
DELIMITER ;
mysql sequence
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转载自ahua186186.iteye.com/blog/2316374
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