[{"_id":"1","ML_PRIORITY":"HIGH","STATUS":"True"},{"_id":"2","ML_PRIORITY":"HIGH","STATUS":""},{"_id":"3","ML_PRIORITY":"HIGH","STATUS":"False"},{"_id":"4","ML_PRIORITY":"MEDIUM","STATUS":""},{"_id":"5","ML_PRIORITY":"Low","STATUS":""}]

db.collection.aggregate([{"$group":{"_id":"$ML_PRIORITY","QUALITYCHECKDONE":{"$sum":{"$cond":[{"$eq":["$STATUS","TRUE"]},1,0]}},"QUALITYCHECKNOTDONE":{"$sum":{"$cond":[{"$eq":["$STATUS",""]},1,0]}},"QUALITYCHECKNOTREQ":{"$sum":{"$cond":[{"$eq":["$STATUS","FALSE"]},1,0]}}}},{"$project":{"_id":0,"ML_PRIORITY":"$_id","QUALITYCHECKDONE":1,"QUALITYCHECKNOTDONE":1,"QUALITYCHECKNOTREQ":1}}])