How-To Deal with Multi-Criteria Queries in 3-Tier Architecture

Question

Assuming a basic 3-Tier application (UI-Service-Data Access) with a total abstraction of Data Access layer (SQL, Xml ...)

The UI applications are composed with Datagrids with multi criteria filters, find etc..

So how-to deal with mutli-criteria queries in this architecture without having to create multiple service methods with all possible criteria as parameters...

Note that UI tier doesn't know how the DAL works.

Answer 1

That is what a DTO is for.