MySQL INSERT IF条件为真

Question

我在MySQL中创建了一个存储例程，我想知道是否有可能使INSERT-IF某些条件为TRUE，ELSE INSERT其他条件。

这是我的查询，但我不断收到＃1064错误（SQL语法错误）。

DECLARE a INT;
DECLARE b INT;
DECLARE changeTypeID INT DEFAULT(0);

SET a = (SELECT roomPrice FROM RPH WHERE tier=1 AND 
startDate = '2018-02-20' AND rTypeID=1);
SET b = (SELECT roomPrice FROM RPH WHERE tier=1 AND 
startDate = '2018-02-20' AND rTypeID=2);

SET changeTypeID = CASE WHEN (a>b) THEN 1 WHEN (a<b) THEN 2 WHEN a=b THEN 3 END;
IF (changeTypeID = 1 OR changeTypeID =2) THEN
(
INSERT INTO TABLE_A (X,Y,Z) VALUES (ID, changeTypeID, createdBy);
)
ELSEIF (changeTypeID = 3) THEN
(
INSERT INTO TABLE_B (P,Q,R) VALUES (ID, rID, createdBy);
)
END IF;

以下是错误消息：

SQL Error (1064): You have an error in your SQL Syntax; check the manual
that corresponds to your MySQL version for the right syntax to use near
'INSERT INTO TABLE_A (X,Y,Z)' at line 19

注意：事先已在例程中声明了insert参数。

任何帮助将不胜感激：）

Answer 1

DECLARE a INT;
DECLARE b INT;
DECLARE changeTypeID INT DEFAULT(0);

SET a = (SELECT roomPrice FROM RPH WHERE tier=1 AND 
startDate = '2018-02-20' AND rTypeID=1);
SET b = (SELECT roomPrice FROM RPH WHERE tier=1 AND 
startDate = '2018-02-20' AND rTypeID=2);

SET changeTypeID = CASE WHEN (a>b) THEN 1 WHEN (a<b) THEN 2 WHEN a=b THEN 3 END;
IF (changeTypeID = 1 OR changeTypeID =2) THEN

INSERT INTO TABLE_A (X,Y,Z) VALUES (ID, changeTypeID, createdBy);

ELSEIF (changeTypeID = 3) THEN

INSERT INTO TABLE_B (P,Q,R) VALUES (ID, rID, createdBy);

END IF;