db={searchResults:[{"_id":ObjectId("625ebcabcc03685c273b2363"),score:12,approved:true,"createdAt":ISODate("2022-04-19T13:44:11.781Z"),"updatedAt":ISODate("2022-04-19T13:44:11.781Z")},{"_id":ObjectId("625ebcabcc03685c273b2364"),score:19,approved:true,"createdAt":ISODate("2022-04-19T13:44:11.781Z"),"updatedAt":ISODate("2022-04-19T13:44:11.781Z")},{"_id":ObjectId("625ebcabcc03685c273b2367"),score:23,approved:true,"createdAt":ISODate("2022-04-19T13:44:11.781Z"),"updatedAt":ISODate("2022-04-19T13:44:11.781Z")}],resourceVote:[{userId:ObjectId("625ebcabcc03685c273b2362"),resourceId:ObjectId("625ebcabcc03685c273b2364"),upDown:"up"},{userId:ObjectId("625ebcabcc03685c273b2362"),resourceId:ObjectId("625ebcabcc03685c273b2367"),upDown:"up"},{userId:ObjectId("625ebcabcc03685c273b2312"),resourceId:ObjectId("625ebcabcc03685c273b2367"),upDown:"up"},{userId:ObjectId("625ebcabcc03685c273b2322"),resourceId:ObjectId("625ebcabcc03685c273b2367"),upDown:"down"},{userId:ObjectId("625ebcabcc03685c273b2352"),resourceId:ObjectId("625ebcabcc03685c273b2367"),upDown:"up"},]}

db.searchResults.aggregate([{$lookup:{from:"resourceVote",let:{resourceId:"$_id",},pipeline:[{$match:{$expr:{$eq:["$resourceId","$$resourceId"]}}},{$group:{_id:0,sum:{$sum:{$cond:[{$eq:["$upDown","up"]},1,-1]}}}},],as:"votes"}},{$addFields:{votes:{"$arrayElemAt":["$votes",0]}}},{"$project":{"wScore":{$ifNull:[{$multiply:["$score","$votes.sum"]},"$score"]},createdAt:1,score:1}}])