You can define your own execution classes. Reasons for doing this include:
EC1, EC2, and EC3 do not accommodate all combinations of attributes that might be useful.
Associating execution objects with a particular group of engines would improve performance.
Use sp_addexeclass to create a user-defined execution classes that have names and attributes you choose. For example, to define a new execution class called DS with a low-priority value that is allowed to run on any engine:
sp_addexeclass DS, LOW, 0, ANYENGINE
Use sp_bindexeclass to associate a user-defined execution class with an execution object, just as you would with a predefined execution class.
