如何通过使用与数组的多个值匹配来从集合中获取对象 . 例如：我在集合中具有以下数据
{ "_id" : ObjectId("512bc95fe835e68f199c8686"), "author" : "dave", "score" : 80, "views" : 100 }
{ "_id" : ObjectId("512bc962e835e68f199c8687"), "author" : "dave", "score" : 85, "views" : 521 }
{ "_id" : ObjectId("55f5a192d4bede9ac365b257"), "author" : "ahn", "score" : 60, "views" : 1000 }
{ "_id" : ObjectId("55f5a192d4bede9ac365b258"), "author" : "li", "score" : 55, "views" : 5000 }
{ "_id" : ObjectId("55f5a1d3d4bede9ac365b259"), "author" : "annT", "score" : 60, "views" : 50 }
{ "_id" : ObjectId("55f5a1d3d4bede9ac365b25a"), "author" : "li", "score" : 94, "views" : 999 }
{ "_id" : ObjectId("55f5a1d3d4bede9ac365b25b"), "author" : "ty", "score" : 95, "views" : 1000 }
现在我得到一个数组作为输入
{"annT","ahn","ty"}
它可以做这样的事情来获取这些作者的所有记录
db.articles.aggregate(
[ { $match : { author : {"annT","ahn","ty"} } } ]
);
这个输入数组长度根据用户选择而变化 . 有没有更好的方法来获取这些记录？比你提前
1 回答
您可以使用
$in运算符再次匹配特定字段的值数组 .