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https://www.cnblogs.com/chanshuyi/p/quick_start_of_mongodb.html

数组查询操作符：$all用法：{ field : {$all:[value1,value2]}}，查询数组中包含指定值的文档，条件的数组是文档中已有数组的子集示例：db.inventory.find({"tags":{$all:["apple"]}},{"_id":0}){ "name" :"t1", "amount" : 16, "tags" : ["apple", "banana" ] }{ "name" :"t3", "amount" : 58, "tags" : ["o.