Data Access Tier:

Data Access Tier is a  class library consisting of set of classes used to encapsulate data access methods like CRUD (CREATE, READ, UPDATE, and DELETE) operations as well as a set of methods to communicate with data store.

Its primary job is to communicate with any data store like XML, RDBMS, or any Text file etc. It does not contain any business logic. It is used to help communicate with data store to fetch and store data.

This library contains a set of classes. The primary purpose of this library is to communicate with  database.This library does not implement any business logic. 

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namespace IDAL

{
 public interface IBluePrintDAL
{
BluePrintInfonfo GetDALVal()
}
}

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interface DAL
 {
public class BluePrintDAL : IBluePrintDAL
{
public BluePrintInfonfo GetDALVal()
        {
           Execute sp to get it
           
            return Bluevendor;
        }
}
} 

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