MC Complete this sentence: In the three-layer architecture, between the external layer and the conceptual/logical layer, there is... The internal layer incorrect Logical data independence correct Physical data independence incorrect No independence, they are basically the same thing incorrect MC Complete the following sentence, choosing the right words on place A and B.

A ...A... data model is the mapping of a ...B... data model to a model that describes which data is stored where and in what format. A: conceptual, B: internal incorrect A: logical, B: internal incorrect A: logical, B: conceptual incorrect A: internal, B: logical correct MC Statement A: The middle layer of the three-layer architecture consists of both the conceptual data model and the logical data model. The logical data model is physically implemented in the internal layer.

Statement B: The top level of the three-layer architecture is the external layer. Views for one or more applications always offer a window on the complete logical model.

Which sentence(s) is/are right? Only sentence A is right correct Only sentence B is right incorrect Neither A or B is right incorrect Sentence A and B are right incorrect MC Statement A: The middle layer of the three-layer architecture consists of both the conceptual data model and the logical data model. The logical data model is physically implemented in the internal layer.

Statement B: The top level of the three-layer architecture is the external layer. Views for one or more applications always offer a window on the complete logical model.

Which sentence(s) is/are right? Only sentence B is right incorrect Sentence A and B are right incorrect Only sentence A is right correct Neither A or B is right incorrect MC Statement A: Physical data independence implies that neither the applications, nor the views or logical data models must be changed when changes are made to the data storage specifications in the internal data model.

Statement B: Logical data independence implies that software applications are minimally affected by changes in the conceptual or logical data model.

Which sentence(s) is/are right? A and B correct Only B incorrect Only A incorrect Neither A or B incorrect MC Which statement is NOT CORRECT? In a file approach to data management, the data definitions are included in each application separately. incorrect The file approach to data management causes the same information to be stored separately for different applications. incorrect In a file approach to data management, a change in the structure of a data file is easily handled because each application has its own data files. correct In a file approach to data management, different applications could be using older and newer versions of the same data. incorrect MC Which statement is NOT CORRECT? In a file approach to data management, a change in the structure of a data file is easily handled because each application has its own data files. correct In a file approach to data management, the data definitions are included in each application separately. incorrect In a file approach to data management, different applications could be using older and newer versions of the same data. incorrect The file approach to data management causes the same information to be stored separately for different applications. incorrect MC Statement A: Physical data independence implies that neither the applications, nor the views or logical data models must be changed when changes are made to the data storage specifications in the internal data model.

Statement B: Logical data independence implies that software applications are minimally affected by changes in the conceptual or logical data model.

Which sentence(s) is/are right? Only A incorrect A and B correct Only B incorrect Neither A or B incorrect MC Which statement is NOT CORRECT? The internal data model represents the data's physical storage details. incorrect In a database approach, applications don't have their own files, but all applications access the same version of the data by interfacing with the DBMS. incorrect It is more cumbersome to query a database system than a file-based system. correct In a file-based approach, every application had its own query and access procedures, even if they wanted to access the same data. incorrect MC Statement A: Physical data independence implies that neither the applications, nor the views or logical data models must be changed when changes are made to the data storage specifications in the internal data model.

Statement B: Logical data independence implies that software applications are minimally affected by changes in the conceptual or logical data model.

Which sentence(s) is/are right? A and B correct Only A incorrect Only B incorrect Neither A or B incorrect