WGU D426 V2 exam questions with answers.

WGU D426 V2 exam questions with answers |\ |\ |\ |\ |\ |\




The relationship (within the relation) that describes how the value of one
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attribute may be used to find the value of another attribute.
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Functional Dependency |\




An attribute that can be used to find the value of another attribute in the
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relation.

Determinant



Value can be used to find the value of every other non-key attribute in the
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table. Unique and minimal.
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Candidate Key |\




Define & manage database structures
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DDL



Adding, deleting, and modifying data - Manipulates data stored in a
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database.

DML



Used to create user accounts, manage permissions and access.
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DCL

,Includes CREATE, DROP, ALTER, TRUNCATE, RENAME
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DDL



A view created and stored on the database. Underlying data is changed and
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also updated in this view. Uses memory space.
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Materialized View |\




Not stored in memory. Only computed when used or accessed.
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Virtual View |\




The data about the data. Describes elements such as columns, names, and
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data type. |\




Metadata



Ordered collection of elements in parentheses.
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Tuple



% of table rows selected by a query
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Hit Ration
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Reads blocks directly, without accessing an index.
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Table Scan |\

, Reads index blocks sequentially in order to locate the needed table blocks.
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Index Scan
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Database repeatedly splits the index in two until it finds a match.
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Binary Search|\




Database object that maps one or more tables to a single file.
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Tablespace



Specifies tables, columns, and keys. Implements database requirements in a
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specific database system. Also called a schema.
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Logical Design |\




Specifies indexes, table structures, and partitions. Specifies how tables are
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organized on storage media. |\ |\ |\




Physical Design |\




Components of a computer system and the relationships between
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components.

Architecture



Interact directly with database users and administrators and send queries to
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the query processor. Includes Connectors & APIs, Workbench, and utility
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programs.