How to sort by the value of number1 plus number2 in the mongodb -


i prepare objects in mongodb.

{number1:123,number2:321} {number1:222,number2:4532}

for example, these have in database. now, want them value of number1 + number2.

how ?

one option no 1 has said here use aggregation framework. better using $where since faster , can sort on return , more such:

db.c.aggregate([     {'$project': {sumfield: {$add: ['$number1', '$number2']}}},     {'$sort': {sumfield: 1}} ]);

like so. better using inbuilt js, plus index , covered query make faster since aggregation, unlike $where can use index.


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