Should DAO objects be Classes or Structs?

I wanted to know from a performance point of v开发者_运维知识库iew, should DAOs be classes or structs?

Taking into consideration that a lot of them might be created and they might be long lived objects.

What are your views and suggestions around the Data Layer design and using structs as DAOs

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THey should be objects.

You should only build structs if you are building a value type. such as: example: id.

Other than that, you should use object for Data access.