MySQL 错误代码：1193。未知的系统变量
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MySQL Error Code: 1193. Unknown system variable
提问by FrancescoN
Ok so i'm working on triggers, and it tells me it(MySQL workbench 5.2) doesn't recognize this variable.
*Error Code: 1193. Unknown system variable error_msg_3*
好的，所以我正在研究触发器，它告诉我它（MySQL 工作台 5.2）无法识别这个变量。
*错误代码：1193。未知系统变量error_msg_3*
I think it would be correct using it in a trigger, please help me
我认为在触发器中使用它是正确的，请帮助我
CREATE TRIGGER controlla_MaxCARDINALITA_INSERT
BEFORE INSERT ON SENTIERO__HA__TAPPA
FOR EACH ROW
BEGIN
DECLARE max_cardinalita INTEGER;
DECLARE error_msg_3 CONDITION FOR SQLSTATE '99003';
SELECT COUNT(*) into max_cardinalita
FROM SENTIERO__HA__TAPPA
WHERE IDsentiero=NEW.IDsentiero;
IF max_cardinalita>=10 THEN
SIGNAL error_msg_3;
SET error_msg_3='INSERT: Il sentiero ha già il massimo numero di tappe consentito';
END IF;
END$$
EDIT ::
编辑 ：：
I tried this, and it seems working
我试过这个，它似乎工作
DECLARE msg VARCHAR(255);
set msg = concat('MyTriggerError: Trying to insert a negative value in trigger_test: ');
signal sqlstate '45000' set message_text = msg;
采纳答案by hjpotter92
According to MySQL docs, the error #1193occurs when you use wrong code for SQLSTATE.
根据MySQL 文档，#1193当您对SQLSTATE.
Message: Unknown system variable %s
消息：未知的系统变量%s
And, as you can see on the same page, the SQLSTATE 99003is not defined.
而且，正如您在同一页面上看到的，99003未定义SQLSTATE 。
