MySQL存储过程异常：一行被执行，另一行被跳过？

Question

我有一个存储过程，用于检查是否有与输入相同的电子邮件地址的用户，如果没有，则会注册一个。

下面是表：

CREATE TABLE IF NOT EXISTS `overkill`.`accounts` (
    `accountID` INT NOT NULL AUTO_INCREMENT , 
    `email` VARCHAR(64) NOT NULL , 
    `firstName` VARCHAR(32) NOT NULL , 
    `lastName` VARCHAR(32) NOT NULL , 
    `passSaltedSHA` BINARY(20) NOT NULL , 
    `salt` BINARY(20) NOT NULL , 
    `gender` ENUM('m','f') NOT NULL , 
    `birthDate` DATE NOT NULL , 
    `regTime` TIMESTAMP NOT NULL , 
    PRIMARY KEY (`accountID`)) 
ENGINE = InnoDB; 

这里是存储过程：

DELIMITER $$ 

CREATE PROCEDURE `overkill`.`registerUser` (
    IN emailIN VARCHAR(64), 
    IN passwordIN VARCHAR(16), 
    IN firstNameIN VARCHAR(32), 
    IN lastNameIn VARCHAR(32), 
    IN birthIN DATE, 
    IN genderIN ENUM('f','m')) 

BEGIN 
    DECLARE existingMailAccLOG INT DEFAULT NULL; 
    DECLARE saltLOC CHAR(40); 
    DECLARE regSuccessLOC BOOLEAN DEFAULT FALSE; 

    SELECT COUNT(*) INTO existingMailAccLOG FROM `overkill`.`accounts` WHERE `accounts`.`email` = emailIN; 

    IF existingMailAccLOG = 0 THEN 
     SET saltLOC = SHA1(rand()); 
     SET regSuccessLOC = TRUE; 
     INSERT INTO `overkill`.`accounts` (`email`, `firstName`, `lastName`, `passSaltedSHA`, `salt`, `gender`, `birthDate`) VALUES(emailIN, firstNameIN, lastNameIn, UNHEX(SHA1(CONCAT(passwordIN, saltLOC))), UNHEX(saltLOC), genderIN, birthIN); 
    END IF; 

    SELECT regSuccessLOC AS `registered`, saltLOC AS `salt`; 
END 

如果我称之为：

CALL registerUser("abc@def.com", "pass", "firstn", "lastn", "2012-01-01", "f"); 

这插入线到accounts表，但流连忘返，我设置IF

SET saltLOC = SHA1(rand()); 
SET regSuccessLOC = TRUE; 

里面这怎么可能正确的价值观？为什么这些行被跳过并且INSERT仍然被执行，没有错误？

Answer 1

尝试在DECLARE关键字后面的变量名称前添加“@”。它可能会导致一些混淆，如下所述：MySQL: @variable vs. variable. Whats the difference? (Part2)和这里：MySQL: @variable vs. variable. Whats the difference?