MongoDB field increment with max condition in update statement

Question

For MongoDB I'm looking for atomic update that will increment field and if that increment will exceeds maximum given number it will stat that maximum number. Same behavior can be achieved with combination of $inc and $min operators but sadly not in one atomic update. Look at example below.

Example document

{
    "_id": 1,
    "i": 0
}

Queries

db.test.update({_id:1}, {$set:{"a":"foo"}, $inc:{i:1}}); db.test.update({_id:1}, {$min:{i:2}});
db.test.update({_id:1}, {$set:{"b":"bar"}, $inc:{i:1}}); db.test.update({_id:1}, {$min:{i:2}});
db.test.update({_id:1}, {$set:{"c":"baz"}, $inc:{i:1}}); db.test.update({_id:1}, {$min:{i:2}});

Result document

{
    "_id": 1,
    "i": 2,
    "a": "foo",
    "b": "bar",
    "c": "baz"
}

Update

Thanks to Christian P answer I realized that I forgot to mention one more condition. I need document to be updated because I need update more fields than is shown in example. In fact I need increment ceiling (maximum) condition in update statement. I've updated my example to make this clear.

Answer 1

You're looking for a findAndModify command:

db.test.findAndModify({
    query: { _id: 1, i: { $lt: 2 } },
    update: { $inc: { i: 1 } }
})

This query will update the document only if i is not greater than your maximum given value..