Question

我有RavenDB设置，通过WebApi层查询。 RavenDb层返回一个IQueriable，在WebApi层中应用OData过滤器。 RavenDB中保存的每个Employee对象都有一个与之关联的Version属性（保存文档时DateTime.UtcNow.Ticks的值）。最近我正在制定一个要求，我可以在一段时间内多次保存同一个Employee（作为单独的实体，它们的属性值不同但具有相同的Id），但我只想根据其Version值获取最新的一个

为了达到这个目的，我使用了MapReduce，如下所述：

public class Employee_Version : AbstractIndexCreationTask<Employee>
{
    public Employee_Version()
    {
        Map = employees => from employee in employees
                           select new Employee
                           {
                               FirstName = employee.FirstName,
                               LastName = employee.LastName,
                               Departments = employee.Departments,
                               Id = employee.Id,
                               Version = employee.Version,
                               ManagerId = employee.ManagerId,
                               EmployeeId=employee.EmployeeId
                           };

        Reduce = results => from result in results
                            group result by result.ManagerId
                                into g
                                select new
                                {
                                    ManagerId = g.OrderByDescending(d => d.Version).First().ManagerId,
                                    Departments = g.OrderByDescending(d => d.Version).First().Departments,
                                    FirstName = g.OrderByDescending(d => d.Version).First().FirstName,
                                    LastName = g.OrderByDescending(d => d.Version).First().LastName,
                                    Version = g.OrderByDescending(d => d.Version).First().Version,
                                    Id = g.OrderByDescending(d => d.Version).First().Id,
                                    EmployeeId = g.OrderByDescending(d => d.Version).First().EmployeeId
                                };
    }
}

Raven存储库代码：

public IQueryable<Employee> GetEmployees(Expression<Func<Employee, bool>> expression)
{
    using (var session = DocumentStore.OpenSession())
    {
        return session.Query<Employee, Employee_Version>().Statistics(out querysStatistics).Where(expression),
    }
}

Web Api图层代码：

Expression<Func<Employee, bool>> managerIdFilter = e => e.ManagerId == 123;
var employeeQueryable = _employeeRepository.GetEmployees(managerIdFilter);
var queryable = modelOptions.ApplyTo(employeeQueryable.Queryable, new ODataQuerySettings
{
    EnableConstantParameterization = false,
    HandleNullPropagation = HandleNullPropagationOption.False
});

当我查询它时：

http://localhost/employee/list？$顶部= 1

我得到以下例外：

内部ExcpetionUrl：\“/ databases / documents / indexes / Document / Version？＆amp; query = ManagerId％3A123＆amp; pageSize = 1＆amp; sort = __ document_id＆amp; SortHint -__ document_id = String \”\ \ \ \ System.ArgumentException：字段'__document_id'未编入索引，无法对未编入索引的字段进行排序

如果没有使用OData过滤器，则相同的查询可以正常工作。

RavenDb - ArgumentException：字段'__document_id'未编入索引，无法对未编制索引的字段进行排序

0 个答案: