[{_id:ObjectId("62b196e43581370007773393"),name:"John",jobs:[{company:"ACME",type:"programmer",technologies:[{level:1,name:"Java"},{level:3,name:"MongoDB"}]},{company:"ACME",type:"accountant",technologies:[{level:1,name:"Mathematics"},{level:3,name:"Financial"}]}]}]

db.collection.update({},[{$set:{"jobs":{$map:{input:"$jobs",in:{$cond:{if:{$and:[{$eq:["$$this.type","programmer"]},{$ne:["$$this.technologies",[]]}]},then:{$mergeObjects:["$$this",{it_technologies:"$$this.technologies.name"}]},else:"$$this"}}}}}}],{upsert:false,multi:true,})