// Test indexed elemmatch of missing field. t = db.jstests_arrayfind5; t.drop(); function check(nullElemMatch) { assert.eq(1, t.find({'a.b': 1}).itcount()); assert.eq(1, t.find({a: {$elemMatch: {b: 1}}}).itcount()); assert.eq(nullElemMatch ? 1 : 0, t.find({'a.b': null}).itcount()); assert.eq(nullElemMatch ? 1 : 0, t.find({a: {$elemMatch: {b: null}}}).itcount()); // see SERVER-3377 } t.save({a: [{}, {b: 1}]}); check(true); t.createIndex({'a.b': 1}); check(true); t.drop(); t.save({a: [5, {b: 1}]}); check(false); t.createIndex({'a.b': 1}); check(false);