[{"_id":{"year_month":"2022-01","client_name":"client A","client_label":"client A","client_code":0,"client_country":"TH","base_curr":"USD","inv_curr":"USD","dest_curr":"HKD"},"total_vol":100000,"total_tran":100}]

db.collection.aggregate([{$project:{_id:0,"year_month":"$_id.year_month","client_name":"$_id.client_name","client_label":"$_id.client_label","client_code":"$_id.client_code","client_country":"$_id.client_country","base_curr":"$_id.base_curr","inv_curr":"$_id.inv_curr","dest_curr":"$_id.dest_curr","total_vol":"$total_vol","total_tran":"$total_tran"}}])