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? Neither A or B is right incorrect Only sentence B is right incorrect Sentence A and B are right incorrect Only sentence A is right correct
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: logical, B: conceptual incorrect A: logical, B: internal incorrect A: conceptual, B: internal incorrect A: internal, B: logical correct
MC Consider this rule: "An employee of a department can never earn more than the manager of the department." This is an example of a: Semantical integrity rule correct Syntactical integrity rule incorrect
MC Which statement is CORRECT? The database state specifies the various data items, their characteristiscs and relationships and is specified during the database design. incorrect The database state changes when data is updated or removed. correct The database state represents the data in the database when the database is first created. incorrect The database is stored in the catalog. incorrect
MC Statement A: DDL is the language used to define the logical data model, but no other data models.
Statement B: SQL is a DML language to retrieve, insert, delete and modify data. It is stored in the catalog.
Which sentence(s) is/are right? Neither A or B correct Only A incorrect A and B incorrect Only B incorrect
MC Statement A: DDL is the language used to define the logical data model, but no other data models.
Statement B: SQL is a DML language to retrieve, insert, delete and modify data. It is stored in the catalog.
Which sentence(s) is/are right? Only B incorrect Neither A or B correct Only A incorrect A and B incorrect
MC Which statement is CORRECT? In a file approach to data management, the data definitions are included in each application separately. correct The database state represents the data in the database when the database is first created. incorrect It is more cumbersome to query a database system than a file-based system. incorrect It is more cumbersome to query a database system than a file-based system. incorrect
MC Which statement is CORRECT? The database state specifies the various data items, their characteristiscs and relationships and is specified during the database design. incorrect The database is stored in the catalog. incorrect The database state changes when data is updated or removed. correct The database state represents the data in the database when the database is first created. incorrect
MC Complete this sentence: In the three-layer architecture, between the external layer and the conceptual/logical layer, there is... Physical data independence incorrect The internal layer incorrect Logical data independence correct 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: internal, B: logical correct A: logical, B: internal incorrect A: logical, B: conceptual incorrect