How many times does a compiled query have to be recompiled during the application life cycle?

Question

On a website, if I have a class:

public class Provider { static readonly Func<Entities, IEnumerable<Tag>> AllTags = CompiledQuery.Compile<Entities, IEnumerable<Tag>> ( e => e.Tags ); public IEnumerable<Tag> GetAll() { using (var db = new Entities()) { return AllTags(db).ToList(); } } } 

On the page I have:

 protected void Page_Load(object sender, EventArgs ev) { (new Provider()).GetAll(); } 

How many times will the request be compiled? Every time a page loads ...? Once in an application ...?

Answer 1

See that it compiled. I would say it once. Why recompile this? Isn't that the point of compiled queries?

Given that the compiled request is static, once per application instance / lifetime. Note. Life times may overlap.

Answer 2

since it is a static member, once when the class is loaded into the application domain.

Answer 3

I would say once per AppDomain, as this is a static variable.

Answer 4

If you define an AllTags query this way, it will be compiled only once. Check out the blog post about compiled requests in web applications and web services Julie Lerman.

Answer 5

http://msdn.microsoft.com/en-us/library/79b3xss3(v=vs.80).aspx#Y696

"Static elements are initialized before the static member is available for the first time, and before the static constructor, if called."

Thus, it will compile a maximum each time the page is loaded. Since your class does not have a static constructor, it should not compile until you gain access to the static member. (According to MSDN.)

However, does this compile? It seems you are trying to load a static member from the generated class.