Data 210 Test 1

Which of the following DBMS types is not a classification based on a data model? Hierarchical DBMS Network DBMS Object-Relational DBMS Cloud DBMS

Cloud DBMS

Which statement is CORRECT? The external layer of a database contains the logical and conceptual data model. It is more cumbersome to query a database system than a file-based system. The query optimizer is not important to differentiate a DBMS upon in terms of competitiveness. 'Chapter' will automatically be removed when 'Book' is removed.

'Chapter' will automatically be removed when 'Book' is removed.

Which variables types are not directly supported in UML? Multivalued variables Composite variables Variables with unique values (similar to key attribute types in the ER model) Derived variables

Variables with unique values (similar to key attribute types in the ER model)

In the movie ER model above, we focus on the binary relationship 'PRODUCES'. Suppose we add an attribute type that indicates the time that each producer spent on producing each movie called 'WORKING HOURS'. Which of the following scenarios is possible? We can add the attribute type 'WORKING HOURS' to the relationship type PRODUCES. We can migrate the attribute type 'WORKING HOURS' to the 'PRODUCER' entity type. We can migrate the attribute type 'WORKING HOURS' to the 'MOVIE' entity type. We can migrate the attribute type 'WORKING HOURS' to either one of the linked entity types.

We can add the attribute type 'WORKING HOURS' to the relationship type PRODUCES.

Which statement is CORRECT? An existence dependent entity type is always a weak entity type. A weak entity type is always existence dependent. An existence dependent entity type always participates in a 1:1 relationship type. A weak entity type can only have one attribute type.

A weak entity type is always existence dependent.

Complete this sentence: In the three-layer architecture, between the external layer and the conceptual/logical layer, there is... No independence, they are basically the same thing Physical data independence The internal layer Logical data independence

Logical data independence

Evaluate the following statements: 1. Record-at-a-time DML means that the query gets recorded from the user at the time the user inputs the query and then gets processed. 2. Record-at-a-time DML means that navigating the database starts with positioning on one specific record and going from there onwards to other records. 3. Set-at-a-time DML means that the query gets set beforehand and then gets processed by the DBMS. 4. Set-at-a-time DML means that many records can be retrieved in one DML statement. 1 and 3 are right 1 and 4 are right 2 and 4 are right 2 and 3 are right

2 and 4 are right

CODASYL is an example of... A Relational DBMS An Object-Oriented DBMS A Hierarchical DBMS A Network DBMS

A Network DBMS

Statement A: An OLTP system is able to cope with real-time, simultaneous transactions which the database server is able to process in a huge volume. Statement B: An OLAP system uses large amounts of operational data to run complex queries on and provide insights for tactical and strategical decision making.Which statement(s) is/are correct? A and B Only A Only B Neither A or B

A and B

Which statement is NOT CORRECT? In a conceptual data model, the data requirements from the business should be captured and modeled. A conceptual data model is implementation dependent. Examples of implementations of logical data models are hierarchical, CODASYL, relational or object-oriented models. A logical data model translates the conceptual data model to a specific implementation environment.

A conceptual data model is implementation dependent.

Which statement is CORRECT? A class is an instance of an object. Information hiding (also referred to as encapsulation) states that the variables of an object can only be accessed through either getter or setter methods. A class only has variables. Inheritance is not supported in Object-Orientation.

Information hiding (also referred to as encapsulation) states that the variables of an object can only be accessed through either getter or setter methods.

Given the ER model above, which of the following statements is CORRECT? A director of a movie can also act in the same movie. Producer is an existence dependent entity type. A movie can have multiple actors, producers and directors. A movie can have as many lead actors as there are in the movie.

A director of a movie can also act in the same movie.

Which statement is NOT CORRECT? In a database approach, there is typically less storage needed compared to the file approach. A file-based approach to data management incurs a strong dependency between the applications and the data In UML, access modifiers can be used to specify who can have access to a variable or method. A file-based approach to data management facilitates concurrency control.

A file-based approach to data management facilitates concurrency control.

Complete the following sentence, choosing the right words on place A and B.When during crash recovery, aborted transactions need to be undone, that is a task of the ...A... The part of the Storage manager that guarantees the ACID properties is the ...B... A: Lock manager, B: Lock manager A: Recovery manager, B: Transaction manager A: Recovery manager, B: Buffer manager A: Lock manager, B: Recovery manager

A: Recovery manager, B: Transaction manager

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: internal A: internal, B: logical A: conceptual, B: internal A: logical, B: conceptual

A: internal, B: logical

Which statement is CORRECT? The EER model has weak entity types, but no existence dependent entity types. According to the EER model, an author can be a reviewer of his/her own peer reviewed paper. According to the EER model, two journals can never have the same title, even when they are being published by different publishers. According to the EER model, a scientific article can be at the same time a peer reviewed paper and a technical report.

According to the EER model, an author can be a reviewer of his/her own peer reviewed paper.

If you want to use a DBMS architecture that can access multiple data sources itself and provides a uniform interface hiding the low-level details, the most appropriate DBMS would be a... Cloud DBMS Client-Server DBMS n-tier DBMS Federated DBMS

Federated DBMS

What concept specifies the various data items, their characteristics and relationships, constraints, storage details, etc. and is specified during the database design? None of these concepts Database state Database model Catalog

Database model

Which one of the following is an example of a DISJOINT and PARTIAL specialisation? HUMAN -> BLONDE + BRUNETTE HUMAN -> LOVES FISH + LOVES MEAT HUMAN -> UNIVERSITY DEGREE + COLLEGE DEGREE HUMAN -> VEGETARIAN + NON-VEGETARIAN

HUMAN -> BLONDE + BRUNETTE

Which statement is NOT CORRECT? In a database approach, there is typically less storage needed compared to the file approach. In a database approach, the data definitions or metadata are stored in the applications accessing the data. In a database approach, maintenance of data and metadata is easier. 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.

In a database approach, the data definitions or metadata are stored in the applications accessing the data.

Which statement is CORRECT? In a file approach to data management, the data definitions are included in each application separately. Logical data independence means that changes in the logical or conceptual data model should not impact the data storage specifications. A weak entity type can only have one attribute type. CODASYL is an example of a hierarchical DBMS.

In a file approach to data management, the data definitions are included in each application separately.

Which statement is CORRECT? In case a ternary relationship type is represented as 3 binary relationship types, then semantics will get lost. A ternary relationship type can always be represented as 3 binary relationship types without loss of semantics. 3 binary relationship types between 3 entity types can always be replaced by 1 ternary relationship type between the 3 participating entity types. A ternary relationship type cannot have attribute types.

In case a ternary relationship type is represented as 3 binary relationship types, then semantics will get lost.

Which statement is NOT CORRECT? In UML, dependency defines a 'using' relationship which states that a change in the specification of a UML modeling concept may affect another modeling concept that uses it. OCL constraints are defined in a procedural way. The changeability property specifies the type of operations which are allowed on either variable values or links. OCL constraints can be used for various purposes such as, to specify invariants for classes, to specify pre- and post-conditions for methods, to navigate between classes, or to define constraints on operations.

OCL constraints are defined in a procedural way.

Statement A: Native XML DBMSs map the hierarchical structure of an XML document to a physical storage structure, because they are able to use the intrinsic structure of an XML document.Statement B: XML-enabled DBMSs are able to store XML data in an integrated and transparent way, because they are able to use the intrinsic structure of an XML document. Which statement(s) is/are correct? A and B Only A Only B Neither A or B

Only A

Statement A: The DDL compiler compiles data definitions specified in DDL. It is possible that there is only 1 DDL with 3 instruction sets. Statement B: The first step of the DDL compiler is to translate the DDL definitions.Which sentence(s) is/are right? A and B Neither A or B Only A Only B

Only A

Statement A: There is no query processor available in procedural DML. Statement B: With procedural DML, the DBMS determines the access path and navigational strategy to locate and modify the data specified in the query.Which sentence(s) is/are right? A and B Neither A or B Only B Only A

Only A

Statement A: In a Hierarchical DBMS, DML is declarative and set oriented with a query processor. Statement B: In a relational DBMS, there is data independence between the conceptual and internal data model. Which statement(s) is/are correct? A and B Only B Only A Neither A or B

Only B

Statement A: The Query Parser optimizes and simplifies a query and then passes it on to the Query Executor. Statement B: In the DBMS architecture, the Storage Manager takes care of concurrency control. Which sentence(s) is/are correct? Only A Only B A and B Neither A or B

Only B

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 Only sentence B is right Sentence A and B are right Only sentence A is right

Only sentence A is right

Which statement is CORRECT? An association is an instance of a link. Qualified associations can be used to represent weak entity types. An association is always bidirectional. Only binary associations are supported in the UML class diagram.

Qualified associations can be used to represent weak entity types.

Consider this rule: "An employee of a department can never earn more than the manager of the department." This is an example of a: Syntactical integrity rule Semantical integrity rule

Semantical integrity rule

Which statement is CORRECT? The database is stored in the catalog. The database state represents the data in the database when the database is first created. The database state specifies the various data items, their characteristiscs and relationships and is specified during the database design. The database state changes when data is updated or removed.

The database state changes when data is updated or removed.

Which statement is NOT CORRECT? The DDL compiler parses DDL statements, checks them for syntactical correctness, translates them into internal format and then registers the data definitions into the catalog. The response time is the time needed to build the conceptual data model. Qualified associations can be used to represent weak entity types. The database state changes when data is updated or removed.

The response time is the time needed to build the conceptual data model.

According to the model, which of the following statements is CORRECT? There are certain supermarket products that are not Fruits&Vegetables, not meat and not non-food. All food products are either Fruits&Vegetables or meat. A meat product does not have any attributes types. A supermarket product can be a food and non-food product at the same time.

There are certain supermarket products that are not Fruits&Vegetables, not meat and not non-food.

A composite aggregation... has a maximum multiplicity of 1 and a minimum multiplicity of 1 at the composite side. has a maximum multiplicity of n and a minimum multiplicity of 0 or 1 at the composite side. has a maximum multiplicity of 1 and a minimum multiplicity of 0 or 1 at the composite side. has a maximum multiplicity of n and a minimum multiplicity of 0 at the composite side.

has a maximum multiplicity of 1 and a minimum multiplicity of 0 or 1 at the composite side.