Unexpected result when casting oid to date

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    • Type: Bug
    • Resolution: Unresolved
    • Priority: Major - P3
    • None
    • Affects Version/s: 8.2.11
    • Component/s: None
    • Query Execution
    • ALL
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      const dbName = 'test';
const testDb = db.getSiblingDB(dbName);
const coll = testDb.oid_future;

function cleanup() {
try \{ db.getMongo().getDB(dbName).dropDatabase(); } catch (e) {}
}

cleanup();
printjson(coll.insert(\{_id: 1, oid: ObjectId('8071be82122d3312074f0300')}));

const doc = coll.aggregate([
{$project: {
_id:0,
iso: \{$dateToString: {date: {$toDate:'$oid'}, format:'%Y-%m-%dT%H:%M:%S.%LZ', timezone:'UTC'}},
ts: \{$toLong: {$toDate:'$oid'}}
}}
]).toArray()[0];

printjson({
expectedIso:'2038-04-15T09:53:06.000Z',
observed:doc,
matchesExpected:doc.iso ==='2038-04-15T09:53:06.000Z'
});

cleanup();
      Show
      const dbName = 'test' ; const testDb = db.getSiblingDB(dbName); const coll = testDb.oid_future; function cleanup() { try \{ db.getMongo().getDB(dbName).dropDatabase(); } catch (e) {} } cleanup(); printjson(coll. insert (\{_id: 1, oid: ObjectId( '8071be82122d3312074f0300' )})); const doc = coll. aggregate ([ {$project: { _id:0, iso: \{$dateToString: { date : {$toDate: '$oid' }, format: '%Y-% m -%dT%H:% M :%S.%LZ' , timezone: 'UTC' }}, ts: \{$toLong: {$toDate: '$oid' }} }} ]).toArray()[0]; printjson({ expectedIso: '2038-04-15T09:53:06.000Z' , observed:doc, matchesExpected:doc.iso === '2038-04-15T09:53:06.000Z' }); cleanup();
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      Hi,

       

      I found that when casting the oid to data, MongoDB sometimes returns an incorrect result.

       

      This is an example:

       

      const dbName = 'test';
const testDb = db.getSiblingDB(dbName);
const coll = testDb.oid_future;

function cleanup() {
try \{ db.getMongo().getDB(dbName).dropDatabase(); } catch (e) {}
}

cleanup();
printjson(coll.insert(\{_id: 1, oid: ObjectId('8071be82122d3312074f0300')}));

const doc = coll.aggregate([
{$project: {
_id:0,
iso: \{$dateToString: {date: {$toDate:'$oid'}, format:'%Y-%m-%dT%H:%M:%S.%LZ', timezone:'UTC'}},
ts: \{$toLong: {$toDate:'$oid'}}
}}
]).toArray()[0];

printjson({
expectedIso:'2038-04-15T09:53:06.000Z',
observed:doc,
matchesExpected:doc.iso ==='2038-04-15T09:53:06.000Z'
});

cleanup();

       

      This is the outputs:

      
{
  expectedIso: '2038-04-15T09:53:06.000Z',
  observed: {
    iso: '1902-03-10T03:24:50.000Z',
    ts: Long('-2140029310000')
  },
  matchesExpected: false
}

       

      When casting oid to date, the first byte are used, which is `80 71 be 82` in this example. The corresponding Unix timestamp is 2154937986, so the UTC time should be 2038-04-15T09:53:06.000Z.

            Assignee:
            Unassigned
            Reporter:
            Chi Zhang (EXT)
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            Watchers:
            6 Start watching this issue

              Created:
              Updated: