CH6.1 Final, Ch8 final, Final Ch4, Ch10 Final Exam

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One objective of selecting a data type is to minimize storage space. T/F

T

84) A procedure is run by calling it by its name.

TRUE

Which of the following are properties of relations? A) Each attribute has the same name. B) No two rows in a relation are identical. C) There are multivalued attributes in a relation. D) All columns are numeric.

no two rows in a relation are identical

70) Combining a table with itself results in a faster query.

FALSE

The 'schema on read' approach often incorporates JSON or XML. T/F

T

A(n) ________ is a component that stores metadata. information repository index data terms

a

________ database specification indicates all the parameters for data storage that are then input to database implementation. A) Logical B) Physical C) Schematic D) Conceptual

physical

The goal of database security is the protection of data from accidental or intentional threats to its integrity and access. T/F

T

69) Correlated subqueries are less efficient than queries that do not use nesting.

TRUE

71) A transaction is the complete set of closely related update commands that must all be done, or none of them done, for the database to remain valid.

TRUE

81) Triggers have three parts: the event, the condition, and the action.

TRUE

85) SQL statements can be included in another language, such as C or Java.

TRUE

A method that speeds query processing by running a query at the same time against several partitions of a table using multiprocessors is called: parallel query processing. perpendicular query processing. multiple partition queries. query optimization.

a

A transversal dependency is a functional dependency between two or more nonkey attributes.

false

An anomaly is a type of flaw in the database server.

false

An enterprise key is a foreign key whose value is unique across all relations.

false

An identifier assigned to an associative entity is also called a cross-relation key.

false

Anomalies do not generally arise out of transitive dependencies.

false

There can be multivalued attributes in a relation.

false

Unlike columns, the rows of a relation may not be interchanged and must be stored in one sequence.

false

When all multivalued attributes have been removed from a relation, it is said to be in: A) first normal form. B) second normal form. C) Boyce-Codd normal form. D) third normal form.

first normal form

An attribute in a relation of a database that serves as the primary key of another relation in the same database is called a: A) link attribute. B) link key. C) foreign key. D) foreign attribute.

foreign key

A constraint between two attributes is called a(n): A) functional relation. B) attribute dependency. C) functional dependency. D) functional relation constraint.

functional dependency

When transforming a one-to-one relationship, a new relation is always created.

galse

A form of database specification which maps conceptual requirements is called: A) logical specifications. B) response specifications. C) security specifications. D) physical specifications.

logical specifications

The need to ________ relations commonly occurs when different views need to be integrated. A) metadata B) system C) drop D) merge

merge

________ are anomalies that can be caused by editing data in tables. A) Insertion B) Deletion C) Modification D) Creation

modification

A rule that states that each foreign key value must match a primary key value in the other relation is called the: A) referential integrity constraint. B) key match rule. C) entity key group rule. D) foreign/primary match rule.

referential integrity constraint

A two-dimensional table of data sometimes is called a: A) group. B) set. C) declaration. D) relation.

relation

Which of the following violates the atomic property of relations? A) Sam B) Hinz C) Sam Hinz D) Atomic

sam hinz

A relation that contains minimal redundancy and allows easy use is considered to be: A) clean. B) simple. C) complex. D) well-structured.

well-structured

Explain what a candidate key is and how it might be used.

A candidate key is an attribute or a combination of attributes that uniquely identifies a row in a relation. A candidate key must be nonredundant and must also uniquely identify each row. When we look at functional dependencies and candidate keys, we can always say that a determinant is always a candidate key.

Discuss the various relational keys.

A primary key uniquely identifies each row of a relation (or table). It can be either a single column or a composite of two or more columns, which is called a composite key. A foreign key allows us to represent the relationship between two tables. A foreign key in one table is generally a reference to a primary key in another table.

51) Using an outer join produces this information: rows that do not have matching values in common columns are not included in the result table. T/F

F

76) MULTISET is similar to the table datatype. T/F

F

80) Triggers can be used to ensure referential integrity, enforce business rules, create audit trails and replicate tables, but cannot call other triggers. T/F

F

82) A function has only input parameters but can return multiple values. T/F

F

86) When a subquery is used in the FROM clause, it is called a denied table. T/F

F

A database management system needs to provide only three basic facilities for backup and recovery of a database: backup facilities, journalizing facilities, and a recovery manager. T/F

F

The philosophical underpinnings of big data are based on schema on write. T/F

F

The target market for Hadoop is small to medium companies using local area networks. T/F

F

The transaction log contains before- and after-images of records that have been modified. T/F

F

There are two principal types of authorization tables: one for subjects and one for facts. T/F

F

72) Transaction integrity commands are not used to identify whole units of database changes that must be completed in full for the database to retain integrity.

FALSE

HP HAVEn integrates HP technologies with open source big data technologies. T/F

T

In a Heap file organization, files are not stored in any particular order. T/F

T

In a sequential file, the records are stored in sequence according to a primary key value. T/F

T

78) A routine is a named set of SQL statements that are considered when a data modification occurs. T/F

F

Live migration from one environment to another in cloud computing is a challenge. T/F

T

The process of managing simultaneous operations against a database so that data integrity is maintained is called ________. Seperate control duplicate control concurrency control

c

Allocating 10 percent over suggested installation space is sufficient for a DBMS. T/F

F

Backward recovery starts with an earlier copy of the database. T/F

F

Denormalization is the process of transforming relations with variable-length fields into those with fixed-length fields. T/F

F

Field-level locks are used quite often. T/F

F

Free range partitioning is a type of horizontal partitioning in which each partition is defined by a range of values for one or more columns in the normalized table. T/F

F

Structured Query Language (SQL) is a set of methodologies, processes, architectures, and technologies that transform raw data into meaningful information. T/F

F

The Information Resource Lexicon System (IRLS) is a computer software tool used to manage and control access to the information repository. T/F

F

The following code is an example of a correlated subquery. SELECT CustomerName, CustomerAddress, CustomerCity, CustomerState,CustomerPostalCode FROM Customer_T WHERE Customer_T.CustomerID = (SELECT Order_T.CustomerIDFROM Order_T WHERE OrderID = 1008); T/F

F

A DBMS may perform checkpoints automatically or in response to commands in user application programs. T/F

T

A view can be built to present only the data to which a user requires access. T/F

T

Along with table scans, other elements of a query can be processed in parallel. T/F

T

An audit trail of transactions and database changes is kept by a journalizing facility. T/F

T

Denormalization almost always leads to more storage space for raw data. T/F

T

Examination and modification of the SQL code in an application may lead to performance improvements. T/F

T

NoSQL databases DO NOT support ACID (atomicity, consistency, isolation, and durability). T/F

T

SQL allows one to calculate linear regressions, moving averages, and correlations without moving the data outside of the database. T/F

T

Sensitivity testing involves ignoring missing data unless knowing a value might significantly change results. T/F

T

The data administrator takes responsibility for the overall management of data resources. T/F

T

The first line of defense for authentication is the use of passwords, which is a one-factor authentication scheme. T/F

T

The NoSQL model that includes a simple pair of a key and an associated collection of values is called a: A) key-value store. B) document store. C) wide-column store. D) graph database.

a

A trigger is a named set of SQL statements that are considered when a data modification occurs. T/F

T

Apache Cassandra is a wide-column NoSQL database management system. T/F

T

Authorization rules are controls incorporated in the data management system that restrict access to data and also restrict the actions that people may take when they access the data. T/F

T

CASE tool-generated information should be fed into repositories. T/F

T

Concurrent transactions need to be processed in isolation so that they do not interfere with each other. T/F

T

Server logs are considered a big data variety data type. T/F

T

Two-phase locking results in a growing phase where locks are acquired and a shrinking phase where locks are released. T/F

T

Value (related to the five 'v's' of big data) addresses the pursuit of a meaningful goal. T/F

T

VarChar2 would be appropriate for a user that wanted a text datatype for LastName that would only consume the required space. T/F

T

62) A correlated subquery is executed once for each iteration through the outer loop.

TRUE

A disadvantage of partitioning is: remote optimization. simplicity. extra space and update time. shorter technology spans.

c

A factor to consider when choosing a file organization is: DDL. DML. efficient storage. inefficient data retrieval.

c

A cloud computing approach in which the service consists mainly of hardware and systems software resources is called: Software-as-a-service. Platform-as-a-service. IDE. Infrastructure-as-a-service.

d

CASE tools can model more complex data relationships, such as ternary relationships.

false

Data integrity consists of powerful operations to manipulate data stored in relations.

false

A transaction that terminates abnormally is called a(n) ________ transaction. terminated completed deleted aborted

d

The UNION clause is used to: A) combine the output from multiple queries into a single result table. B) join two tables together to form one table. C) find all rows that do not match in two tables. D) find all rows that are in one table, but not the other.

a

The ________ operator is used to combine the output from multiple queries into a single result table. Union Divide Collate Intersect

a

The ________ technique involves reprocessing the day's transactions against the backup copy of the database. restore/rerun

a

All of the following are objectives when selecting a data type EXCEPT: improve data integrity. represent all possible values. support all data manipulations. use a lot of storage space.

d

An operation to join a table to itself is called a(n): outer join. sufficient-join. inner join. Self-join

d

An organization using HDFS realizes that hardware failure is a(n): A) norm. B) irregularity. C) anomaly. D) inconsistency.

A

Big data includes: A) large volumes of data with many different data types that are processed at very high speeds. B) large volumes of data entry with a single data type processed at very high speeds. C) large volumes of entity relationship diagrams (ERD) with many different data types that are processed at very high speeds. D) large volumes of entity relationship diagrams (ERD) with a single data type processed at very high speeds.

A

It is true that in an HDFS cluster the DataNodes are the: A) large number of slaves. B) single master servers. C) language libraries. D) business intelligences.

A

MongoDB databases are composed of: A) collections. B) tables. C) rowsets. D) columns.

A

The primary use of Pig is to: A) transform raw data into a format that is useful for analysis. B) query large databases. C) create large databases. D) create data warehouses.

A

________ includes the value of speed in a NoSQL database. A) Velocity B) Vigilant C) Verified D) Variety

A

________ is an important scripting language to help reduce the complexity of MapReduce. A) Pig B) Horse C) Dog D) Cat

A

The three 'v's' commonly associated with big data include: A) viewable, volume, and variety. B) volume, variety, and velocity. C) verified, variety, and velocity. D) vigilant, viewable, and verified.

B

________ generally processes the largest quantities of data. A) Operational databases B) Transaction processing C) Big data D) Data marts

B

According to your text, NoSQL stands for: A) Numbered SQL. B) No SQL. C) Not Only SQL. D) Numeric Only SQL.

C

An organization that requires a graph database that is highly scalable would select the ________ database management system. A) Access B) Excel Spreadsheet C) Neo4j D) Redis

C

At a basic level, analytics refers to: A) collecting data. B) conducting a needs analysis. C) analysis and interpretation of data. D) normalizing data

C

Big data requires effectively processing: A) a single data type (numeric). B) two data types (text and numeric). C) many data types. D) a single data type (text).

C

NoSQL includes data storage and retrieval: A) based on the relational model. B) based on normalized tables. C) not based on the relational model. D) not based on data

C

The NoSQL model that incorporates 'column families' is called a: A) key-value store. B) document store. C) wide-column store. D) column-SQL database.

C

When a data repository (including internal and external data) does NOT follow a predefined schema, this is called a: A) data dump. B) data ocean. C) data lake. D) data stream.

C

Horizontal partitioning refers to the process of combining several smaller relations into a larger table. T/F

F

In order to perform a restore/rerun, the database must be mirrored. T/F

F

JSON is commonly used in conjunction with the 'document store' NoSQL database model. T/F

T

A DBMS periodically suspends all processing and synchronizes its files and journals through the use of a: checkpoint facility. database change log. backup facility. recovery manager.

a

A ________ is a query submitted by a DBA to test the current performance of a database or to predict the response time for queries. Hearbeat query optimize query satisfaction query

a

Controls incorporated into a data management system that restrict access to data are called ________. authorization rules permissions status

a

A join in which rows that do not have matching values in common columns are still included in the result table is called a(n): equi-join. natural join. outer join. union join.

c

A key decision in the physical design process is: deciding on the monitor. deciding the e-r diagrams. selecting structures. ignoring the size of the database.

c

A materialized view is/are: A) a virtual table created dynamically on request by a user. B) an in-line query. C) copies or replica of data based on queries. D) always an exact copy of the source table.

c

A requirement to begin designing physical files and databases is: implementation complete. all datatypes determined normalized relations. physical tables created.

c

A trigger can be used as a security measure in which of the following ways? To conduct a DFD analysis To check for viruses To cause special handling procedures to be executed To design a database

c

A type of join between three tables is called a(n): unnatural join. self-join. ternary join. pinned join.

c

All of the following are advantages to cloud-based computing EXCEPT: no need for initial investment in hardware, physical facilities and systems software. elasticity. ACID support for database as a service. organizations can explore new data management technologies more easily.

c

An integrity control supported by a DBMS is: GUI guards. security. range control. substitute estimates.

c

Controls designed to restrict access and activities are called: schemas. business rules. authorization rules. encryption controls.

c

SQL provides the ________ technique, which involves placing an inner query within the WHERE or HAVING clause of an outer query. grouping union subquery joining

c

SQL-invoked routines can be: contained within a CREATE statement. part of a DCL statement. functions or procedures. part of a DDL statement.

c

The coding or scrambling of data so that humans cannot read them is called ________. hiding. encoding. encryption. demarcation.

c

The following code would include: SELECT Customer_T.CustomerID, CustomerName, OrderID FROM Customer_T LEFT OUTER JOIN Order_T ON Customer_T.CustomerID = Order_T.CustomerID; all rows of the Order_T Table regardless of matches with the Customer_T Table. only rows that match both Customer_T and Order_T Tables. all rows of the Customer_T Table regardless of matches with the Order_T Table. only rows that don't match both Customer_T and Order_T Tables.

c

The most commonly used form of join operation is the: union join. outer join. natural join. equi-join.

c

A cascading delete removes all records in other tables associated with the record to be deleted.

true

A partial functional dependency is a functional dependency in which one or more nonkey attributes are functionally dependent on part (but not all) of the primary key.

true

A primary key is an attribute that uniquely identifies each row in a relation.

true

A referential integrity constraint is a rule that maintains consistency among the rows of two relations.

true

A relation in fifth normal form may not contain any anomalies.

true

A well-structured relation contains minimal redundancy and allows users to manipulate the relation without errors or inconsistencies.

true

All values that appear in a column of a relation must be taken from the same domain.

true

Data structures include data organized in the form of tables with rows and columns.

true

If an identifier is not assigned, the default primary key for an associative relation consists of the two primary key attributes from the other two relations.

true

One property of a relation is that each attribute within a relation has a unique name.

true

Sample data are useful for developing prototype applications and for testing queries.

true

The allowable range of values for a given attribute is part of the domain constraint.

true

When normalizing, the goal is to decompose relations with anomalies to produce smaller, well-structured relations.

true

When two or more attributes describe the same characteristic of an entity, they are synonyms.

true

Discuss why it is important to remove multivalued attributes from a relation.

A multivalued attribute is one that can take on more than one value. According to the definition of a relation, there can be no multivalued attributes. The reason for this will be seen later when the schema is normalized. A multivalued attribute can be resolved by creating a separate instance for each value and repeating the data from the non-multivalued attributes.

Discuss when it is best to create a surrogate key for an associative entity.

A surrogate key should be created when any of the following conditions hold: there is a composite primary key, the natural primary key is inefficient (such as a long name) or the natural primary key is recycled. When you have an associative entity, it is often best to use a surrogate key when you have more than two relations that the associative entity is related to, since the primary key would be a composite of the primary keys of all entities related to the associative entity.

How do you convert weak entities to relations?

A weak entity becomes a relation. However, since a weak entity instance does not exist by itself, we must create a relation with the primary key from the strong relation as the primary key, as well as the identifying attribute.

What is an anomaly, and what are the three types of anomalies?

An anomaly is an error or inconsistency that may result when a user attempts to update a table that contains redundant data. There are three types of anomalies. An insert anomaly occurs when a user attempts to enter new information for part of a table. For example, if we stored customer address with an order. A deletion anomaly occurs when the user wants to delete part of a record but also has to delete related data. A modification anomaly occurs when we have to change the same data in multiple places.

An organization that decides to adopt the most popular NoSQL database management system would select: A) Access. B) MongoDB. C) Neo4j. D) Redis.

B

Apache Cassandra is a leading producer of ________ NoSQL database management systems. A) key-value store B) wide-column C) relational D) graph

B

Big data: A) requires a normalized dataset to 3rd Normal Form. B) does not require a strictly defined data model. C) requires a strictly defined schema. D) requires a normalized dataset to BCNF.

B

Data in MongoDB is represented in: A) JSON. B) BSON. C) CSON. D) SON.

B

When reporting and analysis organization of the data is determined when the data is used is called a(n): A) entity relationship diagram. B) schema binding. C) schema on read. D) cognitive schema.

C

With HDFS it is less expensive to move the execution of computation to data than to move the: A) data to hardware. B) data to systems analysis. C) data to computation. D) data to processes.

C

________ includes concern about data quality issues. A) Velocity B) Vigilant C) Veracity D) Variety

C

Although volume, variety, and velocity are considered the initial three v dimensions, two additional Vs of big data were added and include: A) veracity and verified. B) volume and verified. C) verified and valuable. D) veracity and value

D

An organization that requires a sole focus on performance with the ability for keys to include strings, hashes, lists, and sorted sets would select ________ database management system. A) Access B) Excel Spreadsheet C) Neo4j D) Redis

D

Hive is a(n) ________ data warehouse software. A) Oracle B) Microsoft C) Macintosh D) Apache

D

NoSQL focuses on: A) avoidance of replication of data. B) minimizing storage space. C) normalized data. D) flexibility.

D

The Hadoop Distributed File System (HDFS) is the foundation of a ________ infrastructure of Hadoop. A) relational database management system B) DBBMS C) Java D) data management

D

The NoSQL model that is specifically designed to maintain information regarding the relationships (often real-world instances of entities) between data items is called a: A) key-value store. B) document store. C) wide-column store. D) graph-oriented database

D

Discuss the two major occasions when you benefit from using normalization.

During logical database design, normalization is used as a check and balance to make sure that your E-R diagram is correct as well as your relational schema before doing physical design. Another occasion when you benefit is reverse-engineering an older system, since many of the tables and user views are redundant.

Discuss how you would map a regular entity to a relation.

Each regular entity is transformed into a relation. There are a couple of things that need to be done with some special types of attributes. Composite attributes are broken down into their individual components. Multivalued attributes are broken down into separate relations. For example, if there was a multivalued skill attribute, this would become a skill relation. Also, we ignore derived attributes.

45) An equi-join is a join in which one of the duplicate columns is eliminated in the result table. T/F

F

49) The natural join is very rarely used. T/F

F

Word processing documents are commonly stored in a 'document store' NoSQL database model. T/F

F

58) EXISTS takes a value of false if the subquery returns an intermediate result set.

FALSE

53) There is a special operation in SQL to join a table to itself.

FALSE

60) A subquery in which processing the inner query depends on data from the outer query is called a codependent query.

FALSE

63) Subqueries can only be used in the WHERE clause.

FALSE

65) IF-THEN-ELSE logical processing cannot be accomplished within an SQL statement.

FALSE

74) DBA_USERS contains comments on all tables in an Oracle database.

FALSE

88) User-defined functions can improve system performance because they will be processed as sets rather than individually, thus reducing system overhead.

FALSE

89) Persistent Sorted Modules are extensions defined in SQL-99 that include the capability to create and drop modules of code stored in the database schema across user sessions.

FALSE

46) A join in which the joining condition is based on equality between values in the common column is called a(n) equi-join. T/F

T

55) The following queries produce the same results. select customer_name, customer_city from customer, salesman where customer.salesman_id = salesman.salesman_id and salesman.lname = 'SMITH'; select customer_name, customer_city from customer where customer.salesman_id = (select salesman_id from salesman where lname = 'SMITH') T/F

T

59) When EXISTS or NOT EXISTS is used in a subquery, the select list of the subquery will usually just select all columns as a placeholder because it doesn't matter which columns are returned. T/F

T

64) The UNION clause is used to combine the output from multiple queries into a single result table. T/F

T

66) Figuring out what attributes you want in your query before you write the query will help with query writing. T/F

T

79) Constraints are a special case of triggers. T/F

T

83) The advantages of SQL-invoked routines are flexibility, efficiency, shareability and applicability. T/F

T

87) Establishing IF-THEN-ELSE logical processing within an SQL statement can now be accomplished by using the CASE keyword in a statement. T/F

T

90) A trigger is a named set of SQL statements that are considered when a data modification occurs. T/F

T

A dynamic query is created by the user. T/F

T

Big data databases tend to sacrifice consistency for availability. T/F

T

With a one-key encryption standard, both the sender and the receiver need to know the key that is used to scramble the transmitted or stored data. T/F

T

47) The joining condition of an equi-join is based upon an equality.

TRUE

48) A natural join is the same as an equi-join, except that it is performed over matching columns that have been defined with the same name, and one of the duplicate columns is eliminated.

TRUE

50) An SQL query that implements an outer join will return rows that do not have matching values in common columns.

TRUE

57) In order to find out what customers have not placed an order for a particular item, one might use the NOT qualifier along with the IN qualifier.

TRUE

Discuss how to map a unary one-to-many relationship.

The entity type in the unary relationship is mapped to a relation in the same way as we did for a relation. We next add a foreign key attribute, which maps back to the primary key. This is called a recursive foreign key. So, if we had a relation such as a person supervises one or more persons, the person_id would be a primary key and then there would be a supervisor id which points back to the person_id.

Discuss the types of integrity constraints.

The three major types of integrity constraints are domain constraints, entity integrity and referential integrity. A domain is a set of attributes assigned to an attribute and consists of the domain name, data type, size and allowable values. The entity integrity rule is designed to ensure that every relation has a primary key and that the data values for the primary key are valid (in particular, not null). The referential integrity constraint is a rule that maintains consistency among the rows of two relations. If there is a foreign key in one relation, there must be a matching primary key in the other relation or the foreign key must be null.

Discuss the two possible scenarios when mapping an associative entity.

There are two possible cases for associative entities. In one case, you can have an identifier assigned. You would then use this as the primary key. The other case is where the identifier is not assigned. In this case, you would use the primary keys from the other two (or more) relations that are related to the associative entity.

All of the following are valid datatypes in Oracle 12c EXCEPT: BOOLEAN. VARCHAR2. BLOB. NUMBER.

a

An alternative name for an attribute is called a(n): A) synonym. B) alias. C) alternate attribute. D) related characteristic.

alias

A ________ is a temporary table used in the FROM clause of an SQL query. view table derived table correlated subquery trigger

b

A cloud computing approach in which the service consists of software solutions intended to address the needs of a noncompeting activity is called: Platform-as-a-service. Software-as-a-service. Soft-computing-service. Infrastructure-as-a-service.

b

A detailed coding scheme recognized by system software for representing organizational data is called a(n): DBMS code. data type. SQL. DB layout.

b

A form of denormalization where the same data are purposely stored in multiple places in the database is called: advanced placement. data replication. data duplication. horizontal partitioning.

b

A join that is based upon equality between values in two common columns with the same name and where one duplicate column has been removed is called a(n): multivariate join. natural join. equi-join. inner join.

b

A method for handling missing data is to: delete the associated row. track missing data with special reports. perform insensitivity testing. substitute with random numbers for the missing data.

b

All of the following are common denormalization opportunities EXCEPT: reference data. a one-to-many relationship. two entities with a one-to-one relationship. a many-to-many relationship with nonkey attributes.

b

An advantage of partitioning is: remote optimization. efficiency. increase redundancy. extra space and update time.

b

Establishing IF-THEN-ELSE logical processing within an SQL statement can be accomplished by: using the immediate if statement. using the CASE key word in a statement. using a subquery. using the if-then-else construct.

b

One field or combination of fields for which more than one record may have the same combination of values is called a(n): composite key. secondary key. index. linked key.

b

The MERGE command: is always a single table operation. allows one to combine the INSERT and UPDATE operations. allows one to combine the INSERT and DELETE operations. joins 2 tables together.

b

The ________ DBA view shows information about all users of the database in Oracle. DBA_VIEWS DBA_USERS DBA_INDEXES USERS

b

The logical beginning and end of a transaction is called a ________. transaction completeness transaction boundary transaction defect

b

The smallest unit of application data recognized by system software is a: data type. field. column. row.

b

When incorrect data have been introduced, the database is best recovered by: starting with a new ERD. restarting from the most recent checkpoint and processing subsequent transactions. reloading RDMS software. formatting server.

b

Which type of file is most efficient with storage space? Clustered Sequential Indexed Hashed

b

________ locks allow other transactions to read but not update a record or other resource. private shared public

b

The normal form which removes any remaining functional dependencies because there was more than one primary key for the same nonkeys is called: A) fifth normal form. B) fourth normal form. C) Boyce-Codd normal form. D) sixth normal form.

boyce-codd normal form

The storage format for each attribute from the logical data model is chosen to maximize ________ and minimize storage space. data integration programmer productivity data integrity query design

c

User-defined data types: A) can be a subclass of a standard type. B) can behave as an object. C) can have defined functions and methods. D) can have all of the above.

c

________ is used to undo unwanted database changes. Rollforward Encryption Rollback Restart

c

A primary key that consists of more than one attribute is called a: A) foreign key. B) composite key. C) multivalued key. D) cardinal key.

composite key

In the SQL language, the ________ statement is used to make table definitions. A) create session B) create table C) create index D) select

create table

When a regular entity type contains a multivalued attribute, one must: A) create a single relation with multiple lines for each instance of the multivalued attribute. B) create two new relations, one containing the multivalued attribute. C) create two new relations, both containing the multivalued attribute. D) delete the relation and start over.

create two new relations, one containing the multivalued attribute

A ________ is a DBMS module that restores the database to a correct condition when a failure occurs. transaction logger backup facility restart facility recovery manager

d

A cloud computing approach in which the service consists of infrastructure resources and additional tools that enable application and solution data management solution developers to reach a high level of productivity is called: Tools-as-a-service. Software-as-a-service. Infrastructure-as-a-service. Platform-as-a-service.

d

A method to allow adjacent secondary memory space to contain rows from several tables is called: compiling. cluttering. concatenating. clustering.

d

________ is a component of the relational data model included to specify business rules to maintain the integrity of data when they are manipulated. A) Business rule constraint B) Data integrity C) Business integrity D) Data structure

data integrity

________ problems are encountered when removing data with transitive dependencies. A) Insertion B) Modification C) Deletion D) Merging

deletion

A nonkey attribute is also called a(n): A) column. B) unimportant datum. C) descriptor. D) address.

descriptor

The attribute on the left-hand side of the arrow in a functional dependency is the: A) candidate key. B) determinant. C) foreign key. D) primary key.

determinant

A co-dependency is a constraint between two attributes or two sets of attributes.

false

An attribute that may have more than one meaning is called a(n): A) homonym. B) alias. C) double defined attribute. D) synonym.

homonym

A domain definition consists of all of the following components EXCEPT: A) domain name. B) data type. C) integrity constraints. D) size.

integrity constraints

All of the following are the main goals of normalization EXCEPT: A) minimize data redundancy. B) simplify the enforcement of referential integrity. C) maximize storage space. D) make it easier to maintain data.

maximize storage space

The entity integrity rule states that: A) no primary key attribute can be null. B) referential integrity must be maintained across all entities. C) each entity must have a primary key. D) a primary key must have only one attribute.

no primary key attribute can be null

A relation that contains no multivalued attributes and has nonkey attributes solely dependent on the primary key but contains transitive dependencies is in which normal form? A) First B) Second C) Third D) Fourth

second

54) Joining tables or using a subquery may produce the same result. T/F

t

A functional dependency between two or more nonkey attributes is called a: A) partial functional dependency. B) partial nonkey dependency. C) transitive dependency. D) partial transitive dependency.

transitive dependency

A candidate key is an attribute, or combination of attributes, that uniquely identifies a row in a relation.

true

The columns of a relation can be interchanged without changing the meaning or use of the relation.

true

View integration is the process of merging relations together.

true

When a regular entity type contains a multivalued attribute, two new relations are created.

true

Hive uses ________ to query data. A) SQL B) HiveQL C) BeesNest D) Honeyquery

B

A DBMS must provide journalizing facilities to provide an audit trail of transactions and database changes. T/F

T

A base table is the underlying table that is used to create views. T/F

T

A business owner that needs carefully normalized tables would likely need a relational database instead of a NoSQL database. T/F

T

A materialized view is not persistent. T/F

T

A shared lock allows other transactions to read but not update records in use. T/F

T

The original three 'v's' attributed to big data include volume, variety, and velocity. T/F

T

The repository information model defines types, which should be easy to extend. T/F

T

73) RDBMSs store database definition information in system-created tables which can be considered a data dictionary.

TRUE

A composite key consists of only one attribute.

false

The normal form which deals with multivalued dependencies is called: A) fifth normal form. B) fourth normal form. C) Boyce-Codd normal form. D) sixth normal form.

fourth normal form

Data is represented in the form of: A) data trees. B) tables. C) data notes. D) chairs.

tables

One method to handle missing values is to substitute an exact value. T/F

F

A trigger can be used for security purposes to prohibit inappropriate actions, such as changing a salary value outside of a business day. T/F

T

A domain is a way to create a structure that acts like a table. T/F

F

A file organization is a named portion of primary memory. T/F

F

A repository of information about data is called a catalog. T/F

F

NoSQL focuses on avoidance of replication and minimizing storage space. T/F

F

The granularity of locking is not a critical decision in database design. T/F

F

Correct installation of the DBMS product is essential to any environment. T/F

T

Security is one advantage of partitioning. T/F

T

The ________ occurs when one user reads data that have been partially updated by another user. inconsisten read problem

a

While Oracle has responsibility for managing data inside a tablespace, the tablespace, as a whole, is managed by the: operating system. user. XML. CEO.

a

The primary key of the many side migrates to the one side when transforming a one-to-many relationship.

false

A functional dependency in which one or more nonkey attributes are functionally dependent on part, but not all, of the primary key is called a ________ dependency. A) partial key-based B) partial functional C) cross key D) merged relation

partial function

It is true that in an HDFS cluster the NameNode is the: A) large number of slaves. B) single master server. C) language library. D) business intelligence.

B

NoSQL systems allow ________ by incorporating commodity servers that can be easily added to the architectural solution. A) scaling down B) scaling out C) scaling up D) scaling over

B

NoSQL systems enable automated ________ to allow distribution of the data among multiple nodes to allow servers to operate independently on the data located on it. A) sharing B) sharding C) SQL D) mongo

B

The Hadoop framework consists of the ________ algorithm to solve large scale problems. A) MapSystem B) MapReduce C) MapCluster D) MapComponent

B

________ includes NoSQL accommodation of various data types. A) Velocity B) Vigilant C) Verified D) Variety

D

________ is the most popular key-value store NoSQL database management system. A) Access B) Apache Cassandra C) Neo4j D) Redis

D

Discuss the properties of relations.

Each relation (or table) has a unique name. An entry at the intersection of each row and column is atomic and each row is unique. Each attribute (or column) within a table has a unique name. The sequence of rows and columns is insignificant.

52) One major disadvantage of the outer join is that information is easily lost. T/F

F

68) Specifying the attribute names in the SELECT statement will make it easier to find errors in queries and also correct for problems that may occur in the base system. T/F

F

A deadlock results when two transactions try to read the same record. T/F

F

A default value is the value that a field will always assume, regardless of what the user enters for an instance of that field. T/F

F

Big data allows for two different data types (text and numeric). T/F

F

Economies of storage indicate data storage costs increase every year. T/F

F

Loss of data integrity does not impact the quality of data in a database. T/F

F

MongoDB is a proprietary NoSQL database management system created by Oracle. T/F

F

Neo4j is a wide-column NoSQL database management system developed by Oracle. T/F

F

Transaction processing and management reporting tend to fit big data databases better than relational databases. T/F

F

User-defined functions can improve system performance because they will be processed as sets rather than individually, thus reducing system overhead. T/F

F

Versioning takes the pessimistic approach to locking. T/F

F

67) It is better not to have a result set identified before writing GROUP BY and HAVING clauses for a query.

FALSE

A typical cause of database destruction is a disk crash. T/F

T

Collect everything is a characteristic of a data lake. T/F

T

NoSQL stands for 'Not only SQL.' T/F

T

75) SQL:2008 allows one to calculate linear regressions, moving averages and correlations without moving the data outside of the database.

TRUE

77) Persistent Stored Modules are extensions defined in SQL:1999 that include the capability to add and drop modules of code.

TRUE

Discuss how to map a unary many-to-many relationship.

Two relations are created. One represents the entity type in the relationship, and the other is an associative relation to represent the M:N relationship. The primary key of the associative relation consists of two attributes which take their value from the primary key of the other relation.

Discuss why it is a good idea to create an instance of your relational schema with sample data.

Using sample data allows you to test any assumptions that you may have regarding the design. In addition, it provides a convenient way to check the accuracy of your design and helps to improve communication with users. A final benefit is that you will be able to develop prototype applications and sample queries with the data.

Explain how subtype/supertype relationships are converted to relations.

When we have a supertype/subtype relationship, we need to assign one entity for the supertype and one for each subtype. The supertype has all attributes common to all subtypes as well as a primary key. Each subtype relation has the primary key of the supertype as well as any attributes that are specific to that subtype. Finally, we assign one or more attributes to the supertype to function as subtype discriminators.

In which of the following situations would one have to use an outer join in order to obtain the desired results? A report is desired that lists all customers and the total of their orders. A report is desired that lists all customers and the total of their orders during the most recent month, and includes customers who did not place an order during the month (their total will be zero). A report is desired that lists all customers who placed an order. There is never a situation that requires only an outer join.

b

A discrete unit of work that must be processed completely or not at all within a computer system is called a Journalizing facility. change control device. transaction. before image.

c

In order for two queries to be UNION-compatible, they must: both return at least one row. both have the same number of lines in their SQL statements. both return exactly one row. both output compatible data types for each column and return the same number of rows.

d

In which type of file is multiple key retrieval not possible? Clustered Sequential Indexed Hashed

d

A primary key whose value is unique across all relations is called a(n): A) global primary key. B) inter-table primary key. C) enterprise key. D) foreign global key.

enterprise key

The ________ states that no primary key attribute may be null. A) referential integrity constraint B) entity integrity rule C) partial specialization rule D) range domain rule

entity integrity rule

62) When transforming a weak entity, one should create one relation with both the attributes of the strong entity and the attributes of the weak entity.

false

A foreign key is a primary key of a relation that also is a primary key in another relation.

false

A relation is in first normal form if it has no more than one multivalued attribute.

false

A synonym is an attribute that may have more than one meaning.

false

When transforming a unary many-to-many relationship to relations, a recursive foreign key is used.

false

Which of the following is NOT a reason to create an instance of a relational schema with sample data? A) Sample data can be used to improve user communications. B) Sample data can be used for prototype generation. C) Sample data can reverse database implementation errors. D) Sample data provide a convenient way to check the accuracy of your design.

sample data can reverse database implementation errors

Two or more attributes having different names but the same meaning are called: A) homonyms. B) aliases. C) synonyms. D) alternate attributes.

synonyms

A candidate key must satisfy all of the following conditions EXCEPT: A) the key must uniquely identify the row. B) the key must indicate the row's position in the table. C) the key must be nonredundant. D) each nonkey attribute is functionally dependent upon it.

the key must indicate the row's position in the table

Open-source software always comes with complete documentation. T/F

F

Controls incorporated into a data management system that restrict access to data are called authentication rules. T/F

F

Which of the following functions model business rules? database analysis database design database control

a

In the relational data model, associations between tables are defined through the use of primary keys.

false

The entity integrity rule states that a primary key attribute can be null.

false

The relational data model does, at this time, directly support subtype/supertype relationships.

false

The truncate table statement in SQL creates a new table.

false

61) The following SQL statement is an example of a correlated subquery. select first_name, last_name, total_sales from salesman s1 where total_sales > all (select total_sales from salesman s2 where s1.salesman_id != s2.salesman_id); T/F

T

List and explain 1st, 2nd, 3rd, BCNF, 4th, and 5th normal forms.

There are six different normal forms, all of which build upon each other. When a relation is in first normal form, all repeating groups have been removed. Second normal form means that any partial functional dependencies have been removed. A partial functional dependency occurs when a primary key is a composite key and a nonkey attribute is dependent upon part of the key. A relation is in third normal form when all transitive dependencies have been resolved. A transitive dependency occurs when one nonkey attribute is dependent upon another nonkey attribute. Boyce-Codd normal form removes any further dependencies that may result from anomalies. A relation is in fourth normal form when any dependencies from multivalued attributes have been removed. Fifth normal form removes any further anomalies.

Which of the following functions develop integrity controls? database design database control database implementation

a

Which of the following is an objective of selecting a data type? Improve data integrity Maximize storage space Limit security Represent a small number of possible values

a

Understanding the steps involved in transforming EER diagrams into relations is important because: A) one must be able to check the output of a CASE tool. B) there are rarely legitimate alternatives from which to choose. C) CASE tools can model any situation. D) CASE tools model hypothetical business problems.

one must be able to check the output of a CASE tool

An attribute (or attributes) that uniquely identifies each row in a relation is called a: A) column. B) foreign field. C) primary key. D) duplicate key.

primary key

A credit-card sized plastic card with an embedded microprocessor chip with the ability to store, process and output electronic data in a secure manner is called a(n): smart card. smart chip. e-credit card. secure card.

a

Distributing the rows of data into separate files is called: horizontal partitioning. file allocation. vertical partitioning. normalization.

a

The dive in anywhere characteristic of a data lake overrides constraints related to confidentiality. T/F

F

The following query will execute without errors. select customer.customer_name, salesman.sales_quota from customer where customer.salesman_id = (select salesman_id where lname = 'SMITH'); T/F

F

One decision in the physical design process is selecting structures. T/F

T


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