public void ShouldBuildFirstOrDefaultEnumComparisonPredicateQuery()
        {
            var queryProvider = new QueryProvider <ConvertableModel>();

            var query          = queryProvider.FirstOrDefault(x => x.ConvertableProperty != EnumValue.Unknown);
            var expectedString = $"SELECT ConvertableProperty_c FROM ConvertableModel {_nl}WHERE (ConvertableProperty_c != NULL) {_nl}LIMIT 1{_nl}";

            Assert.AreEqual(expectedString, query);
        }