PHP CodeIgniter WHERE 子句语句

Question

我有一个非常基本的声明，我正在尝试运行但遇到了问题。

$item = $this->db
            ->select("r.CustomerIDs, r.DateAdded")
            ->join("customer_orders_rewards as cor", "r.RewardID = cor.RewardID")
            ->join("customer_orders as co", "co.OrderID = cor.OrderID")
            ->where(array("r.Denomination" => $row['Denomination'], "r.RewardID" => "cor.RewardID"))
            ->get("customer_rewards as r");

在上面的语句中，它将 cor.RewardID 解释为一个字符串，我希望它是来自 join 的字段。

它导致查询看起来像这样:

SELECT `r`.`CustomerID`, `r`.`DateAdded` 
FROM `customer_rewards` as `r` 

JOIN `customer_orders_rewards` as `cor` 
ON `r`.`RewardID` = `cor`.`RewardID` 

JOIN `customer_orders` as `co` 
ON `co`.`OrderID` = `cor`.`OrderID` 

WHERE `r`.`Denomination` = '35' 
AND `r`.`RewardID` = 'cor.RewardID'  <---- Issue

如何在我的 WHERE 子句中引用来自 join 的字段？

Answer 1

一个简单的解决方法是使用

"r.RewardID = cor.RewardID"

代替

"r.RewardID" => "cor.RewardID"

这样，cor.RewardID 不应被视为字符串文字，而应被视为实际列。

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旁注，当 r.RewardID = cor.RewardID 时，您已经加入了行，所以我想说额外的条件是多余的(有问题的条件)，因此不需要.