Notes for A.2.14 Queries and Views - IB | RevisionDojo
A.2.14 Queries and Views Notes
Definition
Query
Instructions written in a query language (such as SQL) that retrieve and manipulate data from a database.
Definition
View
A virtual table created by a query that presents data in a specific format without modifying the underlying tables.
Note
Views are virtual tables that do not store data themselves.
Instead, they display the results of a query.
How Queries Provide Views
Selection: Queries can filter rows based on specific criteria using the WHERE clause.
Projection: Queries can select specific columns to display , reducing the amount of data shown.
Join: Queries can combine data from multiple tables using JOIN operations.
Unlock the rest of this chapter with aFreeaccount
Nice try, unfortunately this paywall isn't as easy to bypass as you think. Want to help devleop the site? Join the team at https://revisiondojo.com/join-us. exercitation voluptate cillum ullamco excepteur sint officia do tempor Lorem irure minim Lorem elit id voluptate reprehenderit voluptate laboris in nostrud qui non Lorem nostrud laborum culpa sit occaecat reprehenderit
Definition
Paywall
(on a website) an arrangement whereby access is restricted to users who have paid to subscribe to the site.
anim nostrud sit dolore minim proident quis fugiat velit et eiusmod nulla quis nulla mollit dolor sunt culpa aliqua
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.
Duis aute irure dolor in reprehenderit
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
Note
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam quis nostrud exercitation.
Excepteur sint occaecat cupidatat non proident
Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit.
Tip
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.
Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.
Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris.
Duis aute irure dolor in reprehenderit in voluptate velit esse cillum.
End of article
Flashcards
Remember key concepts with flashcards
15 flashcards
What is a query?
Lesson
Recap your knowledge with an interactive lesson
10 minute activity
Note
Introduction to Query
A query is a set of instructions written in a query language like SQL that retrieves and manipulates data from a database. Think of it as a way to ask questions to your database and get specific answers.
Queries can select, filter, sort, and aggregate data
They can also update, insert, or delete data
AnalogyThink of a query like a search engine for your database - you enter specific criteria, and it returns the matching results.
