node.js - Undo Unwind in aggregate in mongodb -

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i have multiple data this

{     "_id" : objectid("57189fcd72b6e0480ed7a0a9"),     "venueid" : objectid("56ce9ead08daba400d14edc9"),     "companyid" : objectid("56e7d62ecc0b8fc812b2aac5"),     "cardtypeid" : objectid("56cea8acd82cd11004ee67a9"),     "matchdata" : [          {             "matchid" : objectid("57175c25561d87001e666d12"),             "matchdate" : isodate("2016-04-08t18:30:00.000z"),             "matchtime" : "20:00:00",             "_id" : objectid("57189fcd72b6e0480ed7a0ab"),             "active" : 3,             "cancelled" : 0,             "produced" : 3         },          {             "matchid" : objectid("57175c25561d87001e666d13"),             "matchdate" : isodate("2016-04-09t18:30:00.000z"),             "matchtime" : "20:00:00",             "_id" : objectid("57189fcd72b6e0480ed7a0aa"),             "active" : null,             "cancelled" : null,             "produced" : null         }     ],     "__v" : 0 }

i m doing group companyid , work fine want search in matchdata based on matchtime , matchid purpose $unwind matchdata after unwind using search query this

db.getcollection('matchwisedata').aggregate([ {"$match":{    "matchdata.matchid":{"$in":[objectid("57175c25561d87001e666d12")]} }}, {"$unwind":"$matchdata"}, {"$match":{     "matchdata.matchid":{"$in":[objectid("57175c25561d87001e666d12")]}} }])

its give me proper result after applying unwind there way undo m using unwind search inside subdocument or there other way search inside subdocument.

well can of course use $push , $first in $group document was:

db.getcollection('matchwisedata').aggregate([     { "$match":{        "matchdata.matchid":{"$in":[objectid("57175c25561d87001e666d12")]}     }},     { "$unwind":"$matchdata"},     { "$match":{         "matchdata.matchid":{"$in":[objectid("57175c25561d87001e666d12")]}     }},     { "$group": {         "_id": "$_id",         "venueid": { "$first": "$venueid" },         "companyid": { "$first": "$companyid" },         "cardtypeid": { "$first": "$cardtypeid" },         "matchdata": { "$push": "$matchdata" }     }} ])

but should have used $filter mongodb 3.2 in first place:

db.getcollection('matchwisedata').aggregate([     { "$match":{        "matchdata.matchid":{"$in":[objectid("57175c25561d87001e666d12")]}     }},     { "$project": {         "venueid": 1,         "companyid": 1,         "cardtypeid": 1,         "matchdata": {              "$filter": {                 "input": "$matchdata",                 "as": "match",                 "cond": {                    "$or": [                        { "$eq": [ "$$match.matchid", objectid("57175c25561d87001e666d12") ] }                    ]                 }             }         }     }} ])

and if had @ least mongodb 2.6, still have used $map , $setdifference instead:

db.getcollection('matchwisedata').aggregate([     { "$match":{        "matchdata.matchid":{"$in":[objectid("57175c25561d87001e666d12")]}     }},     { "$project": {         "venueid": 1,         "companyid": 1,         "cardtypeid": 1,         "matchdata": {              "$setdifference": [                 { "$map": {                     "input": "$matchdata",                     "as": "match",                     "in": {                         "$cond": [                            { "$or": [                               { "$eq": [ "$$match.matchid", objectid("57175c25561d87001e666d12") ] }                            ]},                             "$$match",                             false                         ]                     }                 }},                 [false]             ]         }     }} ])

that's fine when every array element has "unique" identifier, "set" operation removes false values $map.

both of ways "filter" content array without using $unwind

n.b: not sure if grasp $in used match "list of conditions" rather being required match on arrays. condition can be:

 "matchdata.matchid": objectid("57175c25561d87001e666d12")

where have single value match on. use $in , $or when have "list" of conditions. arrays make no difference operator required.


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