“COUNT（*）”附近的语法错误？

Question

我想要做一个互动的存储过程 我的意思是，在执行后用户应输入一个字

我写了这一点，但它不工作..

DELIMITER $$ 

DROP PROCEDURE IF EXISTS ric_forn$$ 
CREATE PROCEDURE ric_forn (IN nome_forn VARCHAR(100) , OUT msg VARCHAR(100)) 
BEGIN 
DECLARE num_rec INT; 

IF (nome_forn = '') THEN 
    SET msg = "Attenzione il nome inserito non è valido !"; 
END IF; 

SELECT COUNT (*) INTO num_rec FROM Fornitori WHERE Des_Fornitore = nome_forn; 

IF num_rec = 0 THEN 
    SET msg = "Nessun record trovato !"; 

ELSE 

SELECT Id_Fornitore,Des_Fornitore,Ind_Fornitore WHERE Des_Fornitore = nome_forn; 
    SET msg = "Records trovati:"; 

END IF; 

END$$ 

DELIMITER ; 

我得到这个错误：

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 '*) INTO num_rec FROM Fornitori WHERE Des_Fornitore = nome_forn;

Answer 1

的空间和(*)之间COUNT是显著。你应该把它们放在一起，不要留下空间。

SELECT COUNT(*) INTO ... 

例外是如果你SET SQL_MODE='IGNORE_SPACE'。阅读Function Name Parsing and Resolution了解更多详情。

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你其他错误是，你忘了FROM子句中的查询之一：

SELECT Id_Fornitore,Des_Fornitore,Ind_Fornitore WHERE Des_Fornitore = nome_forn; 

应该是：

SELECT Id_Fornitore,Des_Fornitore,Ind_Fornitore FROM Fornitori 
WHERE Des_Fornitore = nome_forn;