Yii - 使用 createCommand() 和 IF() 的复杂查询

Question

我正在尝试使用 Yii 'queryBuilder' 来构建复杂的 SQL 查询 - 现有查询如下所示：

    $cmd->select('SUM(redeemedCodes.school_points) AS reportingTotalPoints, redeemedCodes.date_redeemed, redeemedCodes.inactive, redeemedCodes.subject_id);
    $cmd->from('redeemed_codes redeemedCodes');

谁能解释如何修改 SELECT 以包含 IF 元素，如下所示： IF(orderProduct.subject_message_link = 1 AND orderProduct.message != '', CONCAT(subject.subject_name, ' ', orderProduct.message), subject.subject_name) AS reportingSubjectName')

这甚至可以在 Yii 中使用 createCommand() 吗？

我正在尝试构建类似于以下的查询：

SELECT redeemedCodes.user_id AS user_id, SUM(redeemedCodes.school_points) AS reportingTotalPoints, 
IF(orderProduct.subject_message_link = 1 AND orderProduct.message != '', CONCAT(subject.subject_name, ' ', orderProduct.message), subject.subject_name) AS reportingSubjectName 
FROM `redeemed_codes` `redeemedCodes`

Answer 1

未测试：

我认为 CDbExpression 可能很方便。

$exp = new CDbExpression("IF(orderProduct.subject_message_link = 1 AND orderProduct.message != '', CONCAT(subject.subject_name, ' ', orderProduct.message), subject.subject_name)");

并在需要放置字符串的任何地方使用 $exp。例如

$sql = "Select *, " . $exp . " as ReportingSubjectName FROM ....";

Answer 2

你可以试试这样的：

$sql = "SELECT redeemedCodes.user_id AS user_id, SUM(redeemedCodes.school_points) AS reportingTotalPoints,         redeemedCodes.date_redeemed, redeemedCodes.inactive, redeemedCodes.subject_id, IF(orderProduct.subject_message_link = 1 AND orderProduct.message != '', CONCAT(subject.subject_name, ' ', orderProduct.message), subject.subject_name) AS reportingSubjectName FROM `redeemed_codes` `redeemedCodes`";

$result = Yii::app()->db->createCommand($sql)->queryAll();