WGU D426 - Data Management Foundations – latest update

WGU D426 - Data Management Foundations –
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latest update
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Data

numeric, textual, visual, or audio information that describes real-world
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systems.

analog

Historically, data was mostly ______________, encoded as continuous
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variations on various physical media.
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digital

Today, data is mostly ______________, encoded as zeros and ones on
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electronic and magnetic media.|\ |\ |\




database

a collection of data in a structured format. In principle, can be stored on
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paper or even clay tablets. In practice, however, modern ones are invariably
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stored on computers.
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database system / database management system / DBMS
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software that reads and writes data in a database. ensure data is secure,
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internally consistent, and available at all times. These functions are
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challenging for large databases with many users, so data base systems are
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complex.

database application|\




software that helps business users interact with database systems.
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database administrator
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,- responsible for securing the database system against unauthorized users.
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- enforces procedures for user access and database system availability.
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database designer |\




determines the format of each data element and the overall database
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structure. Must balance several priorities, including storage, response time,
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and support for rules that govern the data. Since these priorities often
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conflict, database design is technically challenging.
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database programmer |\




develops computer programs that utilize a database.
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database user |\




- a consumer of data in a database.
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request, update, or use stored data to generate reports or information.
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- usually access the database via applications but can also submit queries
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directly to the database system.
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transaction

a group of queries that must be either completed or rejected as a whole.
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Execution of some, but not all, queries results in inconsistent or incorrect
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data.

query processor |\




- interprets queries, creates a plan to modify the database or retrieve data,
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and returns query results to the application.
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- manages connections from multiple users and compiles queries into low-
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level instructions for the storage engine.
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query optimization |\




The query processor performs ______________ to ensure the most efficient
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instructions are executed on the data. |\ |\ |\ |\ |\




indexes

,used by the storage manager to quickly locate data.
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transaction manager |\




ensures transactions are properly executed.
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log

a file containing a complete record of all inserts, updates, and deletes
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processed by the database. |\ |\ |\




relational database |\




stores data in tables, columns, and rows, similar to a spreadsheet.
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SQL

includes statements that read and write data, create and delete tables, and
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administer the database system. |\ |\ |\




big data |\




The growth of the internet in the 1990s generated massive volumes of online
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data, often with poorly structured or missing information.
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NoSQL

The newer non-relational systems, for 'not only SQL', and are optimized for
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big data. |\




Open source |\




software that anyone can inspect, copy, and modify with no licensing fee.
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query

a command for a database that typically inserts new data, retrieves data,
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updates data, or deletes data from a database.
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query language |\




a computer programming language for writing database queries.
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, CRUD

The four common queries are an acronym for Create, Read, Update, and
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Delete data. |\




SELECT

retrieves data from a table. |\ |\ |\ |\




UPDATE

modifies data in a table. |\ |\ |\ |\




CREATE TABLE |\




creates a new table by specifying the table and column names.
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data type |\




Each column is assigned a ______________ that indicates the format of
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column values and can be numeric, textual, or complex.
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database design |\




a specification of database objects such as tables, columns, data types, and
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indexes. Also refers to the process used to develop the specification.
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analysis

specifies database requirements without regard to a specific database system.
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ER diagrams
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depicts entities, relationships, and attributes.
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logical design |\




implements database requirements in a specific database system. specifies
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tables, columns, and keys.
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key

a column used to identify individual rows of a table.
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