By mapping application calls to the persistence layer, the dao provides some specific data operations without exposing details of the database. Dynamic data access object design pattern ceciis 2008. In computer software, a data access object dao is an object that provides an abstract interface to some type of database or other persistence mechanism. Use the table of contents in the left navigation to view the topics in this section. This isolation supports the single responsibility principle. Currentdbmade a comeback in access 95 and is the preferred way of accessing your database.
Using dao for data access in your vb apps techrepublic. When it comes to implementing a data access solution in your vb applications, you currently have three choices. Use a data access object dao to abstract and encapsulate access to business objects in the data source figure 1. Working with data access objects appendix c c w orking with d ata a ccess o bjects 5 if youre an access 2 developer, you might be wondering why the currentdbfunction is being recommended because it was marked as obsolete from access 1. This section of the access vba reference contains documentation for all the objects, properties, methods, and events contained in the access object model. Dao pattern players business logic object within the business domain that needs access to data e. Designing objectoriented software is hard, and designing reusable. The data access object hides the actual data source. Through the method of mapping, the app is able to call the persistence layer and the dao then provides a certain type of data operations. Therefore the data access object can be easily be replaced with an object for a di. The data access object dao pattern tries to decouple the access to data from its under.
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