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db.collection.update({},[{$set:{childrens:{$filter:{input:{$ifNull:["$childrens",[]]},cond:{$ne:["$$this.name","Robert"]}}},students:{$concatArrays:[{$ifNull:["$students",[]]},{$map:{input:{$filter:{input:{$ifNull:["$childrens",[]]},cond:{$eq:["$$this.name","Robert"]}}},in:{$mergeObjects:["$$this",{degree:"Master"}]}}}]}}}],{"multi":true,"upsert":false})