WGU D426 V2 Questions and Answers
1. The relationship (within the relation) that describes how the value of one attribute may be used to find the
value of another attribute.: Functional Depen- dency
2. An attribute that can be used to find the value of another attribute in the relation.: Determinant
3. Value can be used to find the value of every other non-key attribute in the table. Unique and minimal.:
Candidate Key
4. Define & manage database structures: DDL
5. Adding, deleting, and modifying data - Manipulates data stored in a data- base.: DML
6. Used to create user accounts, manage permissions and access.: DCL
7. Includes CREATE, DROP, ALTER, TRUNCATE, RENAME: DDL
8. A view created and stored on the database. Underlying data is changed and also updated in this view. Uses
memory space.: Materialized View
9. Not stored in memory. Only computed when used or accessed.: Virtual View
10.The data about the data. Describes elements such as columns, names, and data type.: Metadata
11.Ordered collection of elements in parentheses.: Tuple
12.% of table rows selected by a query: Hit Ration
13.Reads blocks directly, without accessing an index.: Table Scan
14.Reads index blocks sequentially in order to locate the needed table blocks.: Index Scan
15.Database repeatedly splits the index in two until it finds a match.: Binary Search
16.Database object that maps one or more tables to a single file.: Tablespace
17.Specifies tables, columns, and keys. Implements database requirements in a specific database system. Also
called a schema.: Logical Design
18.Specifies indexes, table structures, and partitions. Specifies how tables are organized on storage media.:
Physical Design
19.Components of a computer system and the relationships between compo- nents.: Architecture
20.Interact directly with database users and administrators and send queries to the query processor. Includes
Connectors & APIs, Workbench, and utility programs.: Tools
21.Interprets queries. Compiles queries into low-level instructions for the storage engine. Creates a plan to
modify the database or retrieve data, and returns query results to the application.: Query Processor
22.Link between tools and query processor: Connection
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, WGU D426 V2 Questions and Answers
23.Creates connections and manages communication between tools and query parser.: Connection Manager
24.Translates the query processor instructions into low-level file system commands that modify or
retrieve data.: Storage Engine
25.Accesses data on storage media. Data stored on storage media and orga- nized in files. Contains 3 types of
data: - User data (tables & indexes) - Log files (record of any changes) - Data dictionary (aka: catalog directory of
tables, columns, keys, indexes in a relational database). One row for each database object.: File System
26.Stores reusable information in main memory.: Cache Manager
27.Retains data blocks from the file system for possible reuse.: Buffer Manager
28.Arranged in hierarchy: Multi-tier architecture
29.Multi-tier consisting of web browsers and web servers communicating over the internet.: Web
architecture
30.A software layer that emulates a complete, independent computing envi- ronment.: Virtual Machine
31.A database offered as a PaaS cloud service.: Cloud Database
32.A statement or proposition from which another statement is inferred.: -
Premise
33.Multiple processors managed by a single operating system instance. Shared memory - share the same
memory and storage media.
Shared storage - share storage media only. Shared nothing: Parallel
Computer
34.Group of computers connected by LAN or WAN: Node
35.Group of nodes connected by a LAN, managed by separate operating system instances. Similar to a
parallel computer.: Cluster
36.Runs on a parallel computer or cluster: Parallel Database
37.Runs on multiple computers connected by a WAN: Distributed Database
38.Updates data on multiple nodes of a distributed database. Two-phase com- mit (nodes receive notice of
update, store update in log, send confirmation, then receive commit). Either all nodes or no nodes must be
successfully updated.: Distributed Transactions
39.Updates data on a single node of a distributed database. Databases that use this are called "eventually
consistent".: Local Transaction
40.States that a distributed database cannot be Consistent, Available, and Petition-tolerant simutaneously.
Availability refers to individual nodes. Con- sistent database - confirms to all rules at all times. Network
partition - forms when a network error prevents nodes from communicating. Petition-tolerant
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1. The relationship (within the relation) that describes how the value of one attribute may be used to find the
value of another attribute.: Functional Depen- dency
2. An attribute that can be used to find the value of another attribute in the relation.: Determinant
3. Value can be used to find the value of every other non-key attribute in the table. Unique and minimal.:
Candidate Key
4. Define & manage database structures: DDL
5. Adding, deleting, and modifying data - Manipulates data stored in a data- base.: DML
6. Used to create user accounts, manage permissions and access.: DCL
7. Includes CREATE, DROP, ALTER, TRUNCATE, RENAME: DDL
8. A view created and stored on the database. Underlying data is changed and also updated in this view. Uses
memory space.: Materialized View
9. Not stored in memory. Only computed when used or accessed.: Virtual View
10.The data about the data. Describes elements such as columns, names, and data type.: Metadata
11.Ordered collection of elements in parentheses.: Tuple
12.% of table rows selected by a query: Hit Ration
13.Reads blocks directly, without accessing an index.: Table Scan
14.Reads index blocks sequentially in order to locate the needed table blocks.: Index Scan
15.Database repeatedly splits the index in two until it finds a match.: Binary Search
16.Database object that maps one or more tables to a single file.: Tablespace
17.Specifies tables, columns, and keys. Implements database requirements in a specific database system. Also
called a schema.: Logical Design
18.Specifies indexes, table structures, and partitions. Specifies how tables are organized on storage media.:
Physical Design
19.Components of a computer system and the relationships between compo- nents.: Architecture
20.Interact directly with database users and administrators and send queries to the query processor. Includes
Connectors & APIs, Workbench, and utility programs.: Tools
21.Interprets queries. Compiles queries into low-level instructions for the storage engine. Creates a plan to
modify the database or retrieve data, and returns query results to the application.: Query Processor
22.Link between tools and query processor: Connection
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, WGU D426 V2 Questions and Answers
23.Creates connections and manages communication between tools and query parser.: Connection Manager
24.Translates the query processor instructions into low-level file system commands that modify or
retrieve data.: Storage Engine
25.Accesses data on storage media. Data stored on storage media and orga- nized in files. Contains 3 types of
data: - User data (tables & indexes) - Log files (record of any changes) - Data dictionary (aka: catalog directory of
tables, columns, keys, indexes in a relational database). One row for each database object.: File System
26.Stores reusable information in main memory.: Cache Manager
27.Retains data blocks from the file system for possible reuse.: Buffer Manager
28.Arranged in hierarchy: Multi-tier architecture
29.Multi-tier consisting of web browsers and web servers communicating over the internet.: Web
architecture
30.A software layer that emulates a complete, independent computing envi- ronment.: Virtual Machine
31.A database offered as a PaaS cloud service.: Cloud Database
32.A statement or proposition from which another statement is inferred.: -
Premise
33.Multiple processors managed by a single operating system instance. Shared memory - share the same
memory and storage media.
Shared storage - share storage media only. Shared nothing: Parallel
Computer
34.Group of computers connected by LAN or WAN: Node
35.Group of nodes connected by a LAN, managed by separate operating system instances. Similar to a
parallel computer.: Cluster
36.Runs on a parallel computer or cluster: Parallel Database
37.Runs on multiple computers connected by a WAN: Distributed Database
38.Updates data on multiple nodes of a distributed database. Two-phase com- mit (nodes receive notice of
update, store update in log, send confirmation, then receive commit). Either all nodes or no nodes must be
successfully updated.: Distributed Transactions
39.Updates data on a single node of a distributed database. Databases that use this are called "eventually
consistent".: Local Transaction
40.States that a distributed database cannot be Consistent, Available, and Petition-tolerant simutaneously.
Availability refers to individual nodes. Con- sistent database - confirms to all rules at all times. Network
partition - forms when a network error prevents nodes from communicating. Petition-tolerant
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