mongodb如何聚合连表查询？
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可以使用mongodb的高级查询$lookup
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>,
as: <output array field>
}
}
其实换成相当于sql语句的join用法
SELECT *, <output array field>
FROM collection
WHERE <output array field> IN (SELECT *
FROM <collection to join>
WHERE <foreignField> = <collection.localField>);
我们以php为例，来编写一个$lookup的聚合查询连表多表示例代码：
<?php
$manager = new MongoDB\Driver\Manager("mongodb://localhost:27017...点击查看剩余70%
by thinkfuture
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