寫作MySQL的功能，但未能

Question

試圖寫在mysql中這個功能，但它給錯誤：

Error Code : 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'IF Per='hour' THEN SET t=Price ; END IF; IF Per='day' THEN SET t=Price/24; END ' at line 8

DELIMITER$$ 
CREATE FUNCTION PricePerHour (Price REAL, Per VARCHAR(5)) 
RETURNS REAL 
DETERMINISTIC 

BEGIN 
DECLARE t REAL; 
IF Price IS NOT NULL AND Per IS NOT NULL 

IF Per='hour' THEN SET t=Price ; END IF; 
IF Per='day' THEN SET t=Price/24; END IF; 
IF Per='week' THEN SET t=Price/7/24; END IF; 
IF Per='month' THEN SET t=Price/30/24; END IF; 
IF Per='year' THEN SET t=Price/365/30/24; END IF; 

RETURN t; 
END IF; 
END $$ 
DELIMITER; 

任何幫助，應該理解。提前Thanx。

Answer 1

失蹤了嗎？

DELIMITER$$ 
CREATE FUNCTION PricePerHour (Price REAL, Per VARCHAR(5)) 
RETURNS REAL 
DETERMINISTIC 

BEGIN 
DECLARE t REAL; 
IF Price IS NOT NULL AND Per IS NOT NULL **THEN** 

IF Per='hour' THEN SET t=Price ; END IF; 
IF Per='day' THEN SET t=Price/24; END IF; 
IF Per='week' THEN SET t=Price/7/24; END IF; 
IF Per='month' THEN SET t=Price/30/24; END IF; 
IF Per='year' THEN SET t=Price/365/30/24; END IF; 

RETURN t; 
END IF; 
END $$ 
DELIMITER;