Entity Framework Loading related entities Eager loading
Example
Eager loading lets you load all your needed entities at once. If you prefer to get all your entities to work on in one database call, then Eager loading is the way to go. It also lets you load multiple levels.
You have two options to load related entities, you can choose either strongly typed or string overloads of the Include method.
Strongly typed.
// Load one company with founder and address details
int companyId = ...;
Company company = context.Companies
.Include(m => m.Founder)
.Include(m => m.Addresses)
.SingleOrDefault(m => m.Id == companyId);
// Load 5 companies with address details, also retrieve country and city
// information of addresses
List<Company> companies = context.Companies
.Include(m => m.Addresses.Select(a => a.Country));
.Include(m => m.Addresses.Select(a => a.City))
.Take(5).ToList();
This method is available since Entity Framework 4.1. Make sure you have the reference using System.Data.Entity; set.
String overload.
// Load one company with founder and address details
int companyId = ...;
Company company = context.Companies
.Include("Founder")
.Include("Addresses")
.SingleOrDefault(m => m.Id == companyId);
// Load 5 companies with address details, also retrieve country and city
// information of addresses
List<Company> companies = context.Companies
.Include("Addresses.Country");
.Include("Addresses.City"))
.Take(5).ToList();
