# IT:AD:EF/CodeFirst:HowTo:Define Models #



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## Summary ##

Although DataAnnotations are easier, do not use them -- they'll drag a dependency on EF to wherever you are using your Db entities (in other words *everywhere*) making your code highly unmaintainable.

All the following uses only the [[IT/AD/Code First/FluentAPI/]] approach in order to isolate the reference to EF to a bootstrapping event in the [[IT/DDD/]] application's infrastructure layer.