CODEWITHSUNDEEP
javamongodbmongodb-java
Mhidy
Mhidy

Reputation: 13

MongoDB Java Driver updates unmatched sub-document

I'm using mongo-java-driver:3.3.0 and trying to update one value of my sub-document using $inc operator and findOneAndUpdate, but only under certain conditions (id comparison and greaterThan filter).

Following is a snippet to reproduce the problem:

    MongoCollection<Document> coll = db.getCollection("update_increase");

    Document docBefore = new Document()
       .append("subdocs", Arrays.asList(
           new Document("id", "AAA").append("count", 10),
           new Document("id", "BBB").append("count", 20)
    ));
    coll.insertOne(docBefore);

    Document filter = new Document()
        .append("subdocs.id", "BBB")
        .append("subdocs.count", new Document("$gt", 7));

    Document update = new Document()
        .append("$inc", new Document("subdocs.$.count", -7));

    Document docAfter = coll.findOneAndUpdate(
        filter,
        update,
        new FindOneAndUpdateOptions().returnDocument(ReturnDocument.AFTER));

docBefore: 

{ "_id" : { "$oid" : "5819c85977a8cb12f8d706c9" },
  "subdocs" : [
      { "id" : "AAA", "count" : 10 },
      { "id" : "BBB", "count" : 20 }
  ] 
}

docAfter:

{ "_id" : { "$oid" : "5819c85977a8cb12f8d706c9" },
  "subdocs" : [
      { "id" : "AAA", "count" : 3 },
      { "id" : "BBB", "count" : 20 }
  ]
}

What I expected is count:13 on the second subdoc (id:"BBB"), but I got an update on the first one (count:3).

This works fine if I remove greaterThan condition line (.. new Document("$gt", 5) ..):

{ "_id" : { "$oid" : "5819c92577a8cb13404cfc91" },
  "subdocs" : [
      { "id" : "AAA", "count" : 10 },
      { "id" : "BBB", "count" : 13 }
  ]
}

What I'm doing wrong?

Thanks!

Upvotes: 1

Views: 295

Answers (1)

s7vr
s7vr

Reputation: 75914

Here is the java equlivant for $elemMatch.

Document filter = new Document("subdocs", new Document().append("$elemMatch", new Document().append("id", "BBB").append("count", new Document("$gt", 7))));

Upvotes: 1

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