Can someone explain to me what I am doing wrong?
I am using Entity Framework 6 with MySQL on a C# application. I have a lot of One to Many relationships, and I need to grab all of the associated data to display it on the screen.
With Lazy Loading, it takes a lot of time to pull the data. I am running this query:
Lot foundLot = EntitiesContext.Lots.Where(x => x.ID == lotID).FirstOrDefault();
Which will return the first lot that matches that ID, and when I call to the subsequent children it will load them. This works fine, however its slow.
I wanted to try to do Eager Loading, but when I call to the "Include" function all of my data is mixed up, and the wrong things get associated.
This is how I am doing that:
Lot foundLot = EntitiesContext.Lots.Where(x => x.ID == lotID)
.Include("Parts")
.Include("Parts.Bin")
.Include("Parts.Stations")
.Include("Parts.Stations.Tools")
.Include("Parts.Stations.Tools.Measurements")
.AsNoTracking()
.FirstOrDefault();
Note: I have also tried using the Include LINQ version
.Include(x => x.Parts.Select(p => p.Stations));
It pulls the Lot, Parts, Bin and Stations correctly but when it pulls the tools it uses the Part ID rather than the associated Station ID.
I have verified my foreign keys are setup properly. I am utilizing Code-First implementation so when I go look at my Tool.cs file:
public int? StationID { get; set; }
[ForeignKey("StationID")]
public virtual Station Station { get; set; }
I define my Foreign Key to the Station ID, and then in my station:
[Key]
public int ID { get; set; }
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
public virtual ICollection<Tool> Tools { get; set; }
and I have a migration that will create my foreign key:
AddForeignKey("tools", "StationID", "stations", "ID", true, "FK_Tools_Stations_StationID");
Like I said, the Lazy Loading everything is fine. It's just slow. The Eager Loading mixes the data, why?
Thank you.
question from:https://stackoverflow.com/questions/66064240/ef-eager-loading-vs-lazy-loading
