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  1. Core Server
  2. SERVER-12674

Possible to end up with an empty string property which can lead to silent troubles

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    • Type: Icon: Bug Bug
    • Resolution: Duplicate
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: 2.4.6
    • Component/s: Write Ops
    • None
    • ALL
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      To get a nameless property from shell:

      db.testGuy.insert({Name: "Test1"})
db.testGuy.update({Name: "Test1"}, {$inc: {"TestObject..Value": 1}})
db.testGuy.findOne({Name: "Test1"})
{
        "Name" : "Test1",
        "TestObject" : {
                "" : {
                        "Value" : 1
                }
        },
        "_id" : ObjectId("52f93e1be856377627267033")
}

      Yikes! Now what happens if I try to mess around with TestObject?

      db.testGuy.update({Name: "Test1"}, {$inc: "TestObject.TestProperty.Value": 1}})
db.testGuy.findOne({Name: "Test1"})
{
        "Name" : "Test1",
        "TestObject" : {
                "" : {
                        "Value" : 1
                }
        },
        "_id" : ObjectId("52f93e1be856377627267033")
}
db.testGuy.update({Name: "Test1"}, {$inc: {VeryCoolValue: 1, "TestObject.AnotherValue": 1}})
{
        "Name" : "Test1",
        "TestObject" : {
                "" : {
                        "Value" : 1
                }
        },
        "VeryCoolValue" : 1,
        "_id" : ObjectId("52f93e1be856377627267033")
}

      That last one shows the danger of this kind of situation: the updates partially complete and report success even though half of my update actually failed.

      Show
      To get a nameless property from shell: db.testGuy.insert({Name: "Test1" }) db.testGuy.update({Name: "Test1" }, {$inc: { "TestObject..Value" : 1}}) db.testGuy.findOne({Name: "Test1" }) { "Name" : "Test1" , "TestObject" : { "" : { "Value" : 1 } }, "_id" : ObjectId( "52f93e1be856377627267033" ) } Yikes! Now what happens if I try to mess around with TestObject? db.testGuy.update({Name: "Test1" }, {$inc: "TestObject.TestProperty.Value" : 1}}) db.testGuy.findOne({Name: "Test1" }) { "Name" : "Test1" , "TestObject" : { "" : { "Value" : 1 } }, "_id" : ObjectId( "52f93e1be856377627267033" ) } db.testGuy.update({Name: "Test1" }, {$inc: {VeryCoolValue: 1, "TestObject.AnotherValue" : 1}}) { "Name" : "Test1" , "TestObject" : { "" : { "Value" : 1 } }, "VeryCoolValue" : 1, "_id" : ObjectId( "52f93e1be856377627267033" ) } That last one shows the danger of this kind of situation: the updates partially complete and report success even though half of my update actually failed.

      Several operations ($set and $inc tested, there may be others) can create a nameless property which becomes difficult to remove and causes updates to partially and silently fail.

            Assignee:
            Unassigned Unassigned
            Reporter:
            jacqueswaller Jacques Waller
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              Created:
              Updated:
              Resolved: