this is the database table
[Table("Score")]
public class Score
{
[Key]
[DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)]
public int ScoreId { get; set; }
public int QuizId { get; set; }
public int PersonId { get; set; }
public string Answer { get; set; }
public virtual Quiz Quiz { get; set; }
}
i want to return a result of how many record exist on database with this code
var query = (from n in db.Scores
where n.PersonId == x && n.Quizid == y
select n).Count();
x and y have a value.
how i can make this code work with 2 conditions?
or any other way to make this work
What you've got should work. A more concise way of writing it would be:
db.Scores.Count(n => n.PersonId == x && n.QuizId == y);
The problem, in terms of compilation, is that Quizid does not exist, it's QuizId.
Related
I am implementing the composite key workaround suggested here:
https://github.com/ServiceStack/ServiceStack.OrmLite/#limitations
but I'm getting the SQL error "Invalid column name 'ID'" when trying to SELECT using the composite key values. SQL Profiler shows that the SELECT does indeed include a column 'ID' so I understand the SQL error. I'm just not sure how to use the workaround without getting the error?
DTO:
public class EmploymentHistory {
[PrimaryKey] // Workaround - Composite Key => Unique Key
public string ID {
get {
return
this.EmployeeID + "|"
+
this.DepartmentID + "|"
+
this.TitleID + "|"
+
this.StartDate.ToString("yyyy-MM-dd");
}
}
public int EmployeeID { get; set; }
public int DepartmentID { get; set; }
public int TitleID { get; set; }
public DateTime StartDate { get; set; }
public DateTime? EndDate { get; set; }
[Ignore]
public Department Department { get; set; }
[Ignore]
public Title Title { get; set; }
}
Request DTO:
[Route("/employmenthistory/{EmployeeID}/{DepartmentID}/{TitleID}/{StartDate}", "GET")]
public class SingleEmploymentHistoryRequest : IReturn<Employee> {
public int EmployeeID { get; set; }
public int DepartmentID { get; set; }
public int TitleID { get; set; }
public DateTime StartDate { get; set; }
}
Service method:
public object Get(SingleEmploymentHistoryRequest request) {
EmploymentHistory employmentHistory = Db.Select<EmploymentHistory>()
.Where(eh =>
eh.EmployeeID == request.EmployeeID
&&
eh.DepartmentID == request.DepartmentID
&&
eh.TitleID == request.TitleID
&&
eh.StartDate.Date == request.StartDate.Date).FirstOrDefault();
if (employmentHistory == null)
throw new WebServiceException("EmploymentHistory not found");
return employmentHistory;
}
You shouldn't need to specify a fake ID primary key for custom queries:
var employmentHistory = Db.Single<EmploymentHistory>(eh =>
eh.EmployeeID == request.EmployeeID &&
eh.DepartmentID == request.DepartmentID &&
eh.TitleID == request.TitleID &&
eh.StartDate >= startDate.Date &&
eh.StartDate < startDate.Date.AddDays(1)));
This question is in reference to the project discussed here. After resolving the previous problem I have run into a new one. When The Student object is saved, the list of courses associated with it is not saved. I can see the collection of course objects when I mouse over the student object after setting a breakpoint:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult AddCourseVM (AddCourseViewModel vModel)
{
Student stu = db.Students.Find(vModel.Student.ID);
foreach (Course c in vModel.PossibleCourses)
{
if (c.Selected)
{
BaseCourse bc = db.BaseCourses.Find(c.BaseCourse.ID);
c.BaseCourse = bc;
c.Student = stu;
stu.CoursesTaken.Add(c);
}
}
if (stu != null)
{
db.Entry(stu).State = EntityState.Modified; //breakpoint here
db.SaveChanges();
}
return RedirectToAction("ListTakenCourses", stu);
}
public ActionResult ListTakenCourses (Student stu)
{
List<Course> taken = stu.CoursesTaken.ToList();
foreach (Course c in taken)
{
c.BaseCourse = db.BaseCourses.Find(c.BaseCourse.ID);
}
ViewBag.CoursesTaken = taken;
return View(stu);
}
But when I pass the object to the next method, the list of courses taken comes back null. The courses are being saved to the database, I can see them when I go into the SQL Server explorer, but for some reason they are not being attached to the student object. The code for the objects:
public class Student
{
public int ID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string WNumber { get; set; }
public int HoursCompleted { get; set; }
public double GPA { get; set; }
public Concentration StudentConcentration { get; set; }
public virtual ICollection<Course> CoursesTaken { get; set; }
public virtual ICollection<Course> CoursesRecommended { get; set; }
}
and:
public class Course
{
public int ID { get; set; }
public string Semester { get; set; }
public Grade? Grade { get; set; }
public bool Selected { get; set; }
public BaseCourse BaseCourse { get; set; }
public Student Student { get; set; }
}
Something that may be important, but that I don't really understand: when I look at the table for the Course object in the database, there are three columns, called Student_ID, Student_ID1, and Student_ID2. I assume they relate to the student associated with the object and the two ways it can be associated (recommended or taken), but the odd thing is that Student_ID is always null, while the other two sometimes have a value and sometimes do not. I have not even begun to implement the recommendation process, so there is no way that list is being filled.
I reworked the classes and now it seems to be working. I changed the Course object to:
public class Course
{
public int ID { get; set; }
public string Semester { get; set; }
public Grade? Grade { get; set; }
public bool Selected { get; set; }
public int BaseCourseID { get; set; }
public int StudentID { get; set; }
public BaseCourse BaseCourse { get; set; }
public Student Student { get; set; }
}
and the controller methods to:
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult AddCourseVM (AddCourseViewModel vModel)
{
Student stu = db.Students.Find(vModel.Student.ID);
foreach (Course c in vModel.PossibleCourses)
{
if (c.Selected)
{
BaseCourse bc = db.BaseCourses.Find(c.BaseCourse.ID);
c.BaseCourse = bc;
c.Student = stu;
stu.CoursesTaken.Add(c);
db.Entry(c).State = EntityState.Added;
}
}
if (stu != null)
{
db.Entry(stu).State = EntityState.Modified;
db.SaveChanges();
}
return RedirectToAction("ListTakenCourses", stu);
}
public ActionResult ListTakenCourses (Student stu)
{
List<Course> taken = db.Courses.Where(c => c.StudentID == stu.ID).ToList();
foreach (Course c in taken)
{
c.BaseCourse = db.BaseCourses.Find(c.BaseCourseID);
c.Student = stu;
stu.CoursesTaken.Add(c);
}
ViewBag.CoursesTaken = taken;
return View(stu);
}
And it is now displaying the courses I add on the next page, but it seems odd that I have to save the child objects separately from the parent and that I have to get the list from the database manually instead of being able to use the object structure. Is this intended behavior, or is there a better way of doing what I'm trying to do (add a list of child objects (courses) to a student object, save the relationship to the database, and then display the list of added objects)?
You are not "passing the object to the next method". You are serializing the object and passing it on the URL, then deserializing it on the other end with this method:
return RedirectToAction("ListTakenCourses", stu);
This is not the way to go about things. What you should be doing is passing a single id, such as the student id. Then, in ListTakenCourses you look up the student again in the database, which if you are doing your query correctly will fully populate the objects.
return RedirectToAction("ListTakenCourses", new { id = stu.StudentID });
public ActionResult ListTakenCourses (int id)
{
List<Course> taken = db.Courses.Where(c => c.StudentID == id).ToList();
//...
}
I am trying to query RavenDB on a Datetime which is being offset by a entry in a collection. As shown below, I have an AppointmentReminder object which contains many AppointmentReminderJobs. I'd like to query for AppointmentReminders where the AppointmentReminderJob is due to run.
My models are as follows:
public class AppointmentReminder
{
public int Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string Email { get; set; }
public string Phone { get; set; }
public DateTime AppointmentDateTime { get; set; }
public ReminderStatus ReminderStatus { get; set; }
public List<AppointmentReminderJob> AppointmentReminderJobs { get; set; }
}
public class AppointmentReminderJob
{
public JobStatus JobStatus { get; set; }
public int DaysPrior { get; set; }
}
My controller and attempt to retrieve a list of AppointmentReminders which have current jobs to run (I know this Where clause isn't complete, but I've tried to simplify it with no luck):
public ActionResult GetJobsQueuedListCurrent()
{
var jobsqueuedlist = RavenSession.Query<AppointmentReminder>()
.Where(appointmentreminder => appointmentreminder.AppointmentReminderJobs.Any(x => appointmentreminder.AppointmentDateTime < DateTime.Now.AddDays(x.DaysPrior)))
.OrderBy(appointmentreminder => appointmentreminder.AppointmentDateTime)
.Take(20)
.ToList();
return View("List", jobsqueuedlist);
}
Calling the above yields a response of:
variable 'x' of type 'ProjectName.Models.AppointmentReminderJob' referenced from scope '', but it is not defined
I am trying to set up an index like so:
public class JobsQueuedListCurrent : AbstractIndexCreationTask<AppointmentReminder, JobsQueuedListCurrent.IndexResult>
{
public class IndexResult
{
public int Id { get; set; }
public DateTime JobDateTime { get; set; }
}
public JobsQueuedListCurrent()
{
Map = appointmentreminders => from appointmentreminder in appointmentreminders
from job in appointmentreminder.AppointmentReminderJobs
select new
{
Id = appointmentreminder.Id,
JobDateTime = appointmentreminder.AppointmentDateTime.AddDays(job.DaysPrior)
};
Store(x => x.Id, FieldStorage.Yes);
Store(x => x.JobDateTime, FieldStorage.Yes);
}
}
Now, I'm querying and getting expected results using:
var jobsqueuedlist = RavenSession.Query<JobsQueuedListCurrent.IndexResult, JobsQueuedListCurrent>()
.Where(x=>x.JobDateTime >= DateTime.Now)
.As<AppointmentReminder>()
.Take(20)
.ToList();
return View("List", jobsqueuedlist);
My last question regarding this would be, my map/index can definitely result in multiple entries of the same document id (appointmentreminder), but my resulting list contains only 1 instance of the document. I'm happy with the way that works, I'm just not sure if I should be performing a reduce or doing something else in my code or just let Raven handle it like it seems like it is doing?
You cannot create such a query. This would require RavenDB to perform computation during query, and that is not allowed.
RavenDB only allows queries on the data in the index.
What you can do it setup the computation in the index, and then query on that.
This is a follow up to an earlier question.
I want to populate a ViewModel, which has 3 properties, and one list of Occ class (which also has 3 properties.
public class RatesViewModel
{
public string TypeName { get; set; }
public long TypeID { get; set; }
public int TypeCount { get; set; }
public virtual IQueryable<Occ> Occs { get; set; }
}
public class Occ
{
public string occ { get; set; }
public decimal ratetocharge { get; set; }
public int numOfOcc { get; set; }
public virtual RatesViewModel RatesViewModel { get; set; }
}
When I run the following Linq query in LinqPad:
var rooms = tblRoom
.GroupBy(p => p.tblType)
.Select(g => new
{
TypeName = g.Key.type_name,
TypeID = g.Key.type_id,
TypeCount = g.Count(),
Occs = rates.Where(rt => rt.type_id == g.Key.type_id &&
(
(rt.type_id == g.Key.type_id)
))
.GroupBy(rt => rt.occ)
.Select(proj => new
{
occ = proj.Key,
ratetocharge = proj.Sum(s => s.rate),
numOfOcc = proj.Count()
})
});
rooms.Dump();
...as before, it correctly returns the data model I'm looking for:
...and when I click on Occs it drills down into the Occs class:
The complete view in LinqPad is:
My query in Visual Studio is:
var rooms = dbr.Rooms
.GroupBy(p => p.RoomTypes).Select(g => new RatesViewModel
{
TypeName = g.Key.type_name,
TypeID = g.Key.type_id,
TypeCount = g.Count()
,
Occs = db.Rates.Where(rt => rt.type_id == g.Key.type_id &&
(
(rt.type_id == g.Key.type_id)
))
.GroupBy(rt => rt.occ)
.Select(proj => new Occ
{
occ = proj.Key,
ratetocharge = proj.Sum(s => s.rate),
numOfOcc = proj.Count()
})
})
.ToList();
However when running this, I get an error:
The specified LINQ expression contains references to queries that are associated with different contexts.
I think I understand the error - but I'm not sure how to separate the query into 2 separate queries, and then join those query results together again to get my original results set.
My model classes are:
public class Rates
{
public int id { get; set; }
public long type_id { get; set; }
public DateTime ratedate { get; set; }
public decimal rate { get; set; }
public string occ { get; set; }
public List<RoomType> Type { get; set; }
}
public class Rental
{
[Key]
public long rental_id { get; set; }
public long room_id { get; set; }
public DateTime check_in { get; set; }
public DateTime check_out { get; set; }
public virtual Room Room { get; set; }
}
public class Room
{
[Key]
public long room_id { get; set; }
public long type_id { get; set; }
public virtual RoomType RoomTypes { get; set; }
public virtual ICollection<Rental> Rentals { get; set; }
}
public class RoomType
{
[Key]
public long type_id { get; set; }
public string type_name { get; set; }
public IQueryable<Rates> Rates { get; set; }
public virtual ICollection<Room> Room { get; set; }
}
Can anyone help either review my query or models, so it works with one query, or show me how to separate the query into two, and then combine the result sets?
Thank you,
Mark
apitest.Models.RoomContext' does not contain a definition for 'Rates'...
(your comment on hydr's answer)
Well, there you go: not only two different context instances but two different context classes. I suspect your linqpad query was directly against the database connection, which means it used one linq-to-sql DataContext (created on the fly).
You need to use one context class (and one instance of it) in your query. And connect to it in Linqpad to make sure you test the same query provider as Visual Studio.
dbr and db seem to be two different instances of the same context. But in one query you should only use one context. So I would suggest the following:
Occs = dbr.Rates.Where(rt => rt.type_id == g.Key.type_id && ....
If this doesn't help can you quote the lines where you initialize the contexts?
is there even a possibility to map this to one entity ?
select x,y,z, (select count(*) from othertable where tableid=table.id) as othertablecount
from table t
i want to map this to a class that looks like this:
public class Stuff
{
public string x { get; set; }
public string y { get; set; }
public string z { get; set; }
public int count { get; set; }
}
No. You should map it properly as a collection and use a projection for querying:
class Stuff
{
...
public virtual ICollection<OtherStuff> { get; set; }
}
var stuffWithCount = from stuff in myContext.Stuff
select new
{
stuff.x, ...
count = stuff.OtherStuff.Count()
};