$match 查询不适用于 mongodb 中的查找数组答案

【问题标题】：$match query not working for lookup array in mongodb$match 查询不适用于 mongodb 中的查找数组
【发布时间】：2018-12-26 11:18:33
【问题描述】：

我在 mongodb 数据库中有两个表

 activityCountTbl contains data like

        {
             "_id": ObjectId("5c234f7e3250041280000ca3"),
             "activityId": ObjectId("5c0e27ee590a06bf08003c33"),
             "weekgroupId": ObjectId("5bfbddbcbb2c5645f8001495"),
             "squadronId": ObjectId("5bfc7b7ebb2c56c320002a0a"),
             "attendingCount": NumberInt(6),
             ....
        }  

        {
             "_id": ObjectId("5c234f7e3250041280000ca3"),
             "activityId": ObjectId("5c0e27ee590a06bf08003c33"),
             "weekgroupId": ObjectId("5bfbddbcbb2c5645f8001496"),
             "squadronId": ObjectId("5bfc7b7ebb2c56c320002a0a"),
             "attendingCount": NumberInt(6),
             ....
        } 
   squadronTbl contains data like

         {
           "_id": ObjectId("5c19ccb7590a060691000554"),
           "squadronCode": "336",
           "squadronName": "336TRS",
         }

         {
           "_id": ObjectId("5c19ccb7590a060691000556"),
           "squadronCode": "337",
           "squadronName": "337TRS",
         }

我将某个周组的特定活动的计数详细信息存储在 activityCountTbl 中。我正在使用 activityCountTbl 对中队Tbl 执行查找用于获取特定周组的中队详细信息。下面的代码不起作用。

当我注释/删除 $query 代码时，它会获取所有周组的所有中队。

        $query = ["ActivityArray.weekgroupId" => new MongoDB\BSON\ObjectID("5bfbddbcbb2c5645f8001495"), "ActivityArray.funRun" => "Yes"];   

        $pipeline = array(
            [
              '$match' => $query
            ],  
            [
              '$lookup' => [
                'from' => 'activityCountTbl',
                'localField' => '_id',
                'foreignField' => 'squadronId',
                'as' => 'ActivityArray'
              ]
            ],
            ['$project' => [
                '_id' => 1.0,
                'squadronName' => 1.0,
                'ActivityArray' => 1.0
            ]],
        );

        return $this->db->squadronTbl->aggregate($pipeline)->toArray();

请帮忙！！！

【问题讨论】：

标签： mongodb mongodb-query aggregation-framework mongodb-php php-mongodb

【解决方案1】：

$query = ["ActivityArray.weekgroupId" => new MongoDB\BSON\ObjectID("5bfbddbcbb2c5645f8001495"), "ActivityArray.funRun" => "Yes"]

$pipeline = array(
    [
      '$match' => []
    ],  
    [
      '$lookup' => [
        'from' => 'activityCountTbl',
        'localField' => '_id',
        'foreignField' => 'squadronId',
        'as' => 'ActivityArray'
      ]
    ],
    [
      '$match' => $query 
    ],
    ['$project' => [
        '_id' => 1.0,
        'squadronName' => 1.0,
        'ActivityArray' => 1.0
    ]],
);

类似的东西

【讨论】：

squadron table 不包含 weekgroup id 字段... weekgroupid 和 funrun 字段是 activityCountTbl 的字段
是的，但是您正在将该聚合发送到中队Tbl 集合，因此您需要对其进行匹配或先进行查找
值 "5bfbddbcbb2c5645f8001495"" 来自另一个表，即问题中未提及的周组表
上述帖子永远不会获取任何数据。请尝试理解我的观点
我现在明白了，所以您可能想在第一次匹配中匹配所有内容，或者只是进行查找并将原始匹配放在查找之后