MYSQL查詢錯誤

Question

語法或查詢有什麼問題？

SET @q=1000; 
SET @p=5.00; 

SELECT @ccount := COUNT(*) FROM 1detail WHERE price>=@p; 
if(@ccount='0') THEN 
INSERT INTO 1detail (price,quantity) VALUES (@p,@q); 

ELSE 

INSERT INTO 2detail (price,quantity) VALUES (@p,@q); 
END IF; 

它給我的錯誤：

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(@ccount='0') THEN INSERT INTO 1detail (price,quantity) VALUES (@p,@q)' at line 1:

要創建表（也正在）：與數字開始

CREATE TABLE 1detail 
(
quantity int, 
price DECIMAL(15,2) 
); 

CREATE TABLE 2detail 
(
quantity int, 
price DECIMAL(15,2) 
); 


INSERT INTO 1detail 
(quantity, price) 
VALUES 
('5', '10'); 

Answer 1

表名需要進行轉義。並且，if僅用於函數，存儲過程和觸發器中。假設這個代碼是「如果」 - 保險箱：

SET @q=1000; 
SET @p=5.00; 

SELECT @ccount := COUNT(*) FROM `1detail` WHERE price>=@p; 
if(@ccount='0') THEN 
INSERT INTO `1detail`(price,quantity) VALUES (@p,@q); 
ELSE 
INSERT INTO `2detail`(price,quantity) VALUES (@p,@q); 
END IF; 

如果沒有，你可以這樣做，因爲兩個插件：

INSERT INTO `2detail`(price,quantity) 
    VALUES (@p, @q) 
    WHERE exists (select 1 from `detail` where price >= @p) 

INSERT INTO `1detail`(price,quantity) 
    VALUES (@p, @q) 
    WHERE not exists (select 1 from `detail` where price >= @p)