How to select where sum of fields is greater than a value in MongoDB -


using mongodb, how write regular sql statement?

select * table (field1+field2+field3) > 1

i've been messing $group, $project, $add, etc. feel i'm dancing around solution can't figure out.

the easiest way using $where (i not telling not possible aggregation)

db.table.find({$where: function() {    return this.field1 + this.field2 + this.field3 > 1    // have handle additional cases if of fields not exist. }}

the pros of is easy , intuitive, whereas cons:

requires database processes javascript expression or function each document in collection.

if need perform kind of searches often, go ahead , create new field have sum of 3 fields stored in , put index on it. downside have increase app logic.


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