$elemMatch w/ positional $ project SBE bug

XMLWordPrintableJSON

    • Type: Bug
    • Resolution: Fixed
    • Priority: Critical - P2
    • 5.3.0, 5.1.2, 5.2.0-rc1
    • Affects Version/s: 5.2.0, 5.1.0
    • Component/s: None
    • None
    • Fully Compatible
    • ALL
    • v5.2
    • Hide 
      (function() {
    'use strict';

function runTest() {
    db.test.drop();
    db.test.insert({ _id: 1, "states": [{x: 1, y: 1}, {x: 2, y: 2}]});
    let result = db.test.runCommand({find: "test", filter: {_id: 1 , states: {"$elemMatch": {x: 1, "y": {"$exists": true}}}}, projection: {"states.$": 1 }, limit: 1, singleBatch: true});
    assert.eq(result.cursor.firstBatch.length, 1, "firstBatch is empty");
    assert.eq(result.cursor.firstBatch[0].states.length, 1, "states array is empty");
    assert.eq(result.cursor.firstBatch[0].states[0].x, 1, "unexpected 'states' document returned");
}

printjson("Run test with SBE disabled");
assert.commandWorked(
    db.adminCommand({setParameter: 1, internalQueryForceClassicEngine: true}));
runTest();

printjson("Run test with SBE enabled");
assert.commandWorked(
    db.adminCommand({setParameter: 1, internalQueryForceClassicEngine: false}));
runTest();
}());
      Show
      (function() { 'use strict' ; function runTest() { db.test.drop(); db.test.insert({ _id: 1, "states" : [{x: 1, y: 1}, {x: 2, y: 2}]}); let result = db.test.runCommand({find: "test" , filter: {_id: 1 , states: { "$elemMatch" : {x: 1, "y" : { "$exists" : true }}}}, projection: { "states.$" : 1 }, limit: 1, singleBatch: true }); assert .eq(result.cursor.firstBatch.length, 1, "firstBatch is empty" ); assert .eq(result.cursor.firstBatch[0].states.length, 1, "states array is empty" ); assert .eq(result.cursor.firstBatch[0].states[0].x, 1, "unexpected 'states' document returned" ); } printjson( "Run test with SBE disabled" ); assert .commandWorked( db.adminCommand({setParameter: 1, internalQueryForceClassicEngine: true })); runTest(); printjson( "Run test with SBE enabled" ); assert .commandWorked( db.adminCommand({setParameter: 1, internalQueryForceClassicEngine: false })); runTest(); }());
    • QE 2021-12-13
    • None
    • 0
    • None
    • None
    • None
    • None
    • None
    • None

      In the above reproduction, the asserts pass with SBE disabled. The first assert in firstBatch.length fails when SBE is enabled.

            Assignee:
            Drew Paroski
            Reporter:
            James Wahlin
            Votes:
            0 Vote for this issue
            Watchers:
            16 Start watching this issue

              Created:
              Updated:
              Resolved: