Question

我有以下MySQL：

select  `car`.`ID` AS `ID`,
    `title`,`text`
    from `car` 
    LEFT JOIN `truck` as bigcar ON bigcar.`ID` = `car`.`truckID` 
    WHERE `ID` ='1';

由于某种原因，我正在

where子句中的列'ID'不明确

出于复杂的代码原因，我不会将别名重命名为其他内容（例如ID2）
这不应该起作用吗？

Answer 1

您需要在where子句中指定用于id的表。否则，查询将不知道要使用哪一个，因为在两个表中具有相同的列名

SELECT
 `car`.`ID` AS `ID`, `title`,`text`
FROM `car` 
LEFT JOIN `truck` as bigcar ON bigcar.`ID` = `car`.`truckID` 
WHERE `car`.`ID` ='1';

或者如果您需要bigcar ID，则必须使用：

WHERE `bigcar`.`ID` ='1'; // not truck but bigcar which is the alias you created

Answer 2

怎么样：

select  `car`.`ID` AS `ID`, 
    `title`,`text` 
    from `car`  
    LEFT JOIN `truck` as bigcar ON bigcar.`ID` = `car`.`truckID`  
    WHERE `car`.`ID` ='1';

Answer 3

错误表示两个表中都存在字段ID。要修复它，您应该为WHERE子句添加一个表别名，例如： - bigcar.ID = 1或car.ID = 1 ......根据需要。

即使使用Alias，MySQL中的模糊列也是如此

3 个答案: