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<!DOCTYPE html>
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<title>TeadLead</title>
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content="About TechLead. Your one-stop-site to build-out a technical foundation you can be proud of." />
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content="Learn for free about computer programming, HTML, CSS, Django, JS, Python and system administrations (Linux and windows), hackings,social engineering, and more. TechLead Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere." />
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content="Learn for free about computer programming, HTML, CSS, Django, JS, Python and system administrations (Linux and windows), hackings,social engineering, and more. TechLead Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere." />
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<li class="breadcrumb-item active" aria-current="page">Database</li>
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<img class="w-full rounded-lg shadow-lg border border-gray-50" src="./assets/imgs/databases.png"
alt="Databases" width="1310" height="873" />
<h1>
<span
class="mt-10 block text-3xl text-center leading-8 font-extrabold tracking-tight text-gray-900 sm:text-4xl">Databases</span>
</h1>
<div class="sm:flex justify-between italic">
<p class="ml-8 sm:ml-0 mt-8 text-lg text-gray-500">
Written
<!-- -->
<!-- --><time datetime="2022-10-19T20:11:01.535891+00:00"></time>
</p>
</div>
</div>
</div>
</div>
<div class="grid grid-cols-1 gap-4">
<section aria-labelledby="author" class="hidden sm:block">
<h2 class="sr-only" id="author">Author</h2>
</section>
</div>
</div>
<div class="grid grid-cols-1 gap-4 items-start lg:grid-cols-3 lg:gap-8">
<div class="grid grid-cols-1 gap-4 lg:col-span-2">
<div class="mt-6 prose prose-blue prose-lg text-gray-500 max-w-7xl mx-auto px-6 sm:px-6 lg:px-8 w-full">
<h2 id="introduction-to-databases">
Introduction to databases
</h2>
<!-- -->
<p>
A database is a collection of data that can be stored and
accessed or updated at any point in time by computers.
</p>
<!-- -->
<p>
If you were to compare computers to a human brain, databases
would be the "long term memory" section of the
brain.
</p>
<!-- -->
<p>
When you put data in a database it can always be retrieved
in the future unless it's explicitly been updated,
deleted, or something unexpected has happened to the
computer it's running on.
</p>
<!-- -->
<p>
All that said, there are many different types of databases
-- each with their own strengths and weaknesses and
best-suited to different use cases.
</p>
<!-- -->
<h2 id="types-of-databases">Types of databases</h2>
<!-- -->
<p>
There are many different types of databases, but we'll
just focus on three in this high-level overview:
</p>
<!-- -->
<ul>
<!-- -->
<li>Relational databases</li>
<!-- -->
<li>Object-oriented databases</li>
<!-- -->
<li>Column-oriented databases</li>
<!-- -->
</ul>
<!-- -->
<h3 id="relational-databases">Relational databases</h3>
<!-- -->
<p>
Relational databases are the most common type of database
and are used to store data in tables.
</p>
<!-- -->
<p>
In relational databases tables hold information in rows and
each row corresponds to a single record.
</p>
<!-- -->
<p>
If you're unfamiliar with a database table, you can
think of them as being quite similar (visually) to an Excel
spreadsheet.
</p>
<!-- -->
<p>
Relational databases allow for quick retrieval of data
because each table is indexed by a unique column value,
which can also be used or referenced in other tables to
create relationships between different types of data.
</p>
<!-- -->
<p>
Additionally, relational databases offer more security than
other types of databases as they require access to specific
columns in order to modify or delete records.
</p>
<!-- -->
<h3 id="object-oriented-databases">
Object-oriented databases
</h3>
<!-- -->
<p>
Object-oriented databases are used to store data as objects,
which can be more efficient than storing data in tables but
provides fewer "guard rails" than relational
databases to prevent users from making mistakes.
</p>
<!-- -->
<p>
Objects are organized into classes that represent specific
business concepts and the objects within those classes
inherit properties from their parent class.
</p>
<!-- -->
<p>
This means that no matter what object you create, it will
have certain common features (such as an ID property)
defined by the object's class definition.
</p>
<!-- -->
<p>
Because objects are self-contained, you don't need
access to another object's underlying tables or fields
when working with them; instead, all interaction with an
object occurs through its methods and properties.
</p>
<!-- -->
<p>
Additionally, inheritance allows you to easily create
complex hierarchies of objects without needing to write code
explicitly governing how relationships among objects should
work.
</p>
<!-- -->
<h3 id="column-oriented-databases">
Column-oriented databases
</h3>
<!-- -->
<p>
Column-oriented databases are used to store data in columns,
which can be more efficient than storing data in rows.
</p>
<!-- -->
<p>
Columns correspond one-to-one with records stored in a table
and every column is automatically assigned a primary key
value when the database is created.
</p>
<!-- -->
<p>
Unlike row-based storage systems where every record must
contain information about every column included in the
table, column-based storage systems allow for greater
efficiency as only those records which actually use a given
column will include that column's value(s).
</p>
<!-- -->
<p>
This allows for faster searches across large datasets since
only the relevant records will need be retrieved rather than
reading all of the data in a table before finding the record
you're looking for.
</p>
<!-- -->
<p>How to choose the right database for your project</p>
<!-- -->
<p>
Choosing the right databases is all about weighing the pros
and cons of each of your choices and thinking critically
about what your constraints and priorities are.
</p>
<!-- -->
<p>Here are some key questions to consider:</p>
<!-- -->
<ul>
<!-- -->
<li>
<strong>What kind of data do you need to store?</strong>
Are there many different types of data with complicated
relationships? If so, a relational database might be the
right pick for you. But maybe an object-oriented database
could be a good fit if your data is simple and unlikely to
change in the future.
<!-- -->
</li>
<!-- -->
<li>
<strong>Are "bugs" are no big deal for you or are
they catastrophic and completely unacceptable?</strong>
If the cost of having a bug isn't significant,
object-oriented databases might be a good light-weight
solution for you. But if it's critical that you have
all possible safety in place to avoid bugs, a relational
database might be a better fit.
<!-- -->
</li>
<!-- -->
</ul>
<!-- -->
<p>
Additionally, it's worth considering your
project's scalability when choosing a database. Will
your project need to handle a lot of data or traffic?
</p>
<!-- -->
<p>
However - when in doubt - though it might take a bit more
work upfront, it's usually a safer bet to go with a
mature SQL database like PostgreSQL.
</p>
</div>
</div>
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<h2 class="sr-only" id="table-of-contents">
Table of Contents
</h2>
<div>
<div
class="rounded-lg bg-indigo-50 overflow-hidden shadow-xl border border-indigo-100 mt-4 h-fit top-0 sticky mx-4 sm:mx-0">
<div class="p-6">
<p class="text-center font-semibold text-gray-600 text-lg">
Table of Contents
</p>
<ol class="mt-8 flex flex-col">
<li
class="ml-5 text-gray-600 hover:font-semibold my-2 underline decoration-indigo-500 hover:decoration-indigo-300 hover:decoration-2 self-start h4">
<a href="#introduction-to-databases">Introduction to databases</a>
</li>
<li
class="ml-5 text-gray-600 hover:font-semibold my-2 underline decoration-indigo-500 hover:decoration-indigo-300 hover:decoration-2 self-start h4">
<a href="#types-of-databases">Types of databases</a>
</li>
<li
class="ml-10 text-gray-600 hover:font-semibold my-2 underline decoration-indigo-500 hover:decoration-indigo-300 hover:decoration-2 self-start h5">
<a href="#relational-databases">Relational databases</a>
</li>
<li
class="ml-10 text-gray-600 hover:font-semibold my-2 underline decoration-indigo-500 hover:decoration-indigo-300 hover:decoration-2 self-start h5">
<a href="#object-oriented-databases">Object-oriented databases</a>
</li>
<li
class="ml-10 text-gray-600 hover:font-semibold my-2 underline decoration-indigo-500 hover:decoration-indigo-300 hover:decoration-2 self-start h5">
<a href="#column-oriented-databases">Column-oriented databases</a>
</li>
</ol>
</div>
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<div class="text-center">
<h2 class="text-3xl tracking-tight font-extrabold text-gray-900 sm:text-4xl">
Learn More About Databases
</h2>
<p class="mt-3 max-w-2xl mx-auto text-xl text-gray-500 sm:mt-4"></p>
</div>
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<a class="flex flex-col rounded-lg shadow-lg overflow-hidden" href="/databases/mysql">
<div class="flex-shrink-0">
<img class="h-48 w-full object-cover" src="./assets/imgs" width="413" height="192" alt="MySQL" />
</div>
<div class="flex-1 bg-white p-6 flex flex-col justify-between">
<div class="flex-1">
<div class="block mt-2">
<p class="text-xl font-semibold text-gray-900">MySQL</p>
<p class="mt-3 text-base text-gray-500 line-clamp-2">
Learn about one of the world's most popular SQL
databases: MySQL.
</p>
</div>
</div>
<div class="mt-6 flex items-center">
<div class="flex space-x-1 text-sm text-gray-500">
<p>Last Updated</p>
<time datetime="2022-11-06T00:00:00+00:00"></time>
</div>
</div>
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