web - 3-tier architecture business logic layer without logic -

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hello working on school project in making web application. have pretty understanding 3-tier architecture, in business logic layer (bll) have no logic. using of raw data retrieve data access layer (dal) display in presentation layer (pl). in controller classes, i'm calling mapper facade classes methods without doing further. question is:

is right way it, know dal must never speak directly pl , vise versa, or should call controllers else more describing?

furthermore have made controller class each entity, if have methods in between 2 entities meaning access both entity classes.

it pretty rare in real application database maps 1-1 presentation layer. there normalization sql databases, or denormalization nosql dbs. also, business layer needs user identity security , such doesn't map directly database representation.

the last point made single controller knowing 2 entities fine. why not directly using entities in presentation layer. can mash entities ui can more use, , keep them separated @ data access layer.


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