从不同的数据库获取数据 ASP.NET MVC

Question

In my ASP.NET MVC application, I want to get data from two contexts and merge it and pass it to the view.

Currently, I did this,

private zSqlLink dbs = new zSqlLink();
private zSqlData db = new zSqlData();

public ActionResult PendingSelfTasks() 
{
    IEnumerable <SelfCareTasks> pendingTasks = new List <SelfCareTasks> ();

    var list = dbs.SelfCareTasks.ToList().Where(x => x.Is_Service_Accepted == false && x.Status == true);

    var TaskList = (
        from d in list join c in db.Customer on d.Customer_Id equals c.Id 
        join ser in db.Services on d.Service_Id equals ser.Id 
        where d.Is_Service_Accepted == false && d.Status == true 
        select new SelfCareTasks 
        {
            Id = d.Id,
            CustomerName = c.Sur_Name + c.Name,
            ServiceName = ser.Service_NameEng,
            ServicePrice = d.Service_Price,
        }).ToList();

    return View(TaskList);
}

What I did was, 1st I created list and get the main records from one context and stored them there, Then I create another list and there I joined the list with the other database values to get the data required. Here for the list I'm getting the data and when I merge it with another context returns without data.

Is something I'm doing wrong here?

Answer 1

I'm not sure what your model relations are but as you already know you can't make collective query to different databases. You need to make separate queries to each database and map the datа in the code. Of course based on the answer of Panagiotis Kanavos you can have other different opinions

private zSqlLink dbs = new zSqlLink();
private zSqlData db = new zSqlData();

public ActionResult PendingSelfTasks() 
{
    //Get the collections from databases separately 
    var list = dbs.SelfCareTasks.Where(x => x.Is_Service_Accepted == false && x.Status == true).ToList();

    var listIds = list.Select(x => x.Id).Tolist();
    var customer = bd.Customer.Where(x => listIds.Contains(x.Id)).ToList();

    //Them map all you need in the code
    foreach(var selfCareTasks in list)
    {
    }
    
    return View(TaskList);
}