mongodb javascript：只有匹配子文檔的返回文檔

Question

任何人都知道如何在javascript中僅匹配子文檔返回文檔？

例如這裏是數據庫中的記錄：

[ 
    {"name":"bestbuy",notes:["article IT", "article 2"]}, 
    {"name":"microsoft",notes:["article IT", "another IT", "article 5"]}, 
    {"name":"IBM",notes:["article 8", "article 9"]} 
] 

這裏是我的查詢：

collection.find({"company.notes":/IT/}, function(err,result){}) 

結果是：

[ 
    {"name":"bestbuy",notes:["article IT", "article 2"]}, 
    {"name":"microsoft",notes:["article IT", "another IT", "article 5"]}, 
] 

但我預期的結果是：

[ 
    {"name":"bestbuy",notes:["article IT"]}, 
    {"name":"microsoft",notes:["article IT", "another IT"]} 
] 

任何想法？ 感謝

Answer 1

可以使用聚合

db.collection.aggregate([ 
    {$match: {"notes": /IT/}}, 
    {$unwind: "$notes"}, 
    {$match: {notes: /IT/}}, 
    {$group: {_id: '$_id', name: {$first: '$name'}, notes: {$push: '$notes'}}}, 
    {$project: {'name': 1, 'notes': 1, _id: 0}} 
]) 

收率：

{ "name" : "microsoft", "notes" : [ "article IT", "another IT" ] } 
{ "name" : "bestbuy", "notes" : [ "article IT" ] } 

[只檢索MongoDB中集合的對象陣列中的查詢元件]（HTTP的