.png){kind=logo}
WGU D426 V2
45 studiers today 4.9 (176 reviews) Students also studied Terms in this set (160) Western Governors UniversityD 333 Save D426 Study Guide (Red Text ONLY) 225 terms brattynnPreview C839v5/D334 Additional Practice Teacher 165 terms ShawnD_Preview
WGU - D426: Objective Assessment...
151 terms natesoundslike Preview D426 v Teacher Tas The relationship (within the relation) that describes how the value of one attribute may be used to find the value of another attribute.Functional Dependency
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
An attribute that can be used to find the value of another attribute in the relation.Determinant
Value can be used to find the value of every other non- key attribute in the table. Unique and minimal.Candidate Key
Define & manage database structuresDDL
Adding, deleting, and modifying data - Manipulates data stored in a database.
DML
Used to create user accounts, manage permissions and access.
DCL
Includes CREATE, DROP, ALTER, TRUNCATE, RENAME DDL
A view created and stored on the database. Underlying data is changed and also updated in this view. Uses memory space.Materialized View
Not stored in memory. Only computed when used or accessed.Virtual View
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
The data about the data. Describes elements such as columns, names, and data type.Metadata
Ordered collection of elements in parentheses. Tuple
% of table rows selected by a queryHit Ration
Reads blocks directly, without accessing an index. Table Scan
Reads index blocks sequentially in order to locate the needed table blocks.Index Scan
Database repeatedly splits the index in two until it finds a match.Binary Search
Database object that maps one or more tables to a single file.Tablespace
Specifies tables, columns, and keys. Implements database requirements in a specific database system. Also called a schema.Logical Design
Specifies indexes, table structures, and partitions.Specifies how tables are organized on storage media.Physical Design
Components of a computer system and the relationships between components.Architecture
Interact directly with database users and administrators and send queries to the query processor. Includes Connectors & APIs, Workbench, and utility programs.Tools
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
Link between tools and query processorConnection
Creates connections and manages communication between tools and query parser.Connection Manager
- multiple choice options
- multiple choice options
Translates the query processor instructions into low-level file system commands that modify or retrieve data.Storage Engine
Accesses data on storage media. Data stored on storage
media and organized 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
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
Stores reusable information in main memory.Cache Manager
Retains data blocks from the file system for possible reuse.Buffer Manager
Arranged in hierarchyMulti-tier architecture
Multi-tier consisting of web browsers and web servers communicating over the internet.Web architecture
A software layer that emulates a complete, independent computing environment.Virtual Machine
A database offered as a PaaS cloud service.Cloud Database
A statement or proposition from which another statement is inferred.Premise
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
Group of computers connected by LAN or WAN Node
Group of nodes connected by a LAN, managed by separate operating system instances. Similar to a parallel computer.Cluster
Runs on a parallel computer or clusterParallel Database
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
- multiple choice options
Runs on multiple computers connected by a WAN Distributed Database
Updates data on multiple nodes of a distributed database. Two-phase commit (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
Updates data on a single node of a distributed database.Databases that use this are called "eventually consistent".Local Transaction
States that a distributed database cannot be Consistent, Available, and Petition-tolerant simutaneously. Availability refers to individual nodes. Consistent database - confirms to all rules at all times. Network partition - forms when a network error prevents nodes from communicating.Petition-tolerant - database that continues to function when a network partition occurs.CAP Theorem
Maintains two or more replicas on separate storage
devices. Advantages: High availability, fast concurrent
reads, local reads. Disadvantages: Slow or inconsistent
updates.Replicated database
- multiple choice options
- multiple choice option
- multiple choice option
- multiple choice options
Entire catalog resides on a single nodeCentral Catalog
Copy of catalog resides on each nodeReplicated Catalog
Volatile- Used to conduct daily business -Changes in real time -Detailed Designed for specific business function - Concerned primarily with current data Operational Data
AKA: Reporting Data or Decision Support Data -
Enterprise-wide- Used to understand, manage, and plan the business- Summary Updated at fixed intervals and summarized by time period -Combines data from many business functions -Usually contains current and historic data Analytic Data
- multiple choice options
- multiple choice options
Data warehouse designed for specific business area Data Mart
.png)