方式一 :
db.test.aggregate([
{
$project:{
fields1: 1,
fields2: 1,
difference: { $eq: ["$fields1", "$fields2"]}
},
},
{
$match: {
difference: true
},
},
{ $limit:10 }
]);
方式二:
db.test.find({
"$where": "this.fields1 == this.fields2"
}).limit(10);