Mysql Basico

Tutorials Point, Simply Easy Learning
MySQL Tutorial
Tutorialspoint.com
MySQL is the most popular Open Source Relational SQL database management
system.
MySQL is one of the best RDBMS being used for developing web based software
applications. This tutorial gives an initial push to start you with MySQL. For more
detail kindly check tutorialspoint.com/mysql

What is Database?
A databaseis a separate application that stores a collection of data. Each database has one or
more distinct APIs for creating, accessing, managing, searching, and replicating the data it
holds.
Other kinds of data stores can be used, such as files on the file system or large hash tables in
memory but data fetching and writing would not be so fast and easy with those type of systems.
So now a days weuse relational database management systems (RDBMS) to store and manager
huge volume of data. This is called relational database because all the data is stored into
different tables and relations are established using primary keys or other keys known as foreign
keys.
A Relational DataBase Management System (RDBMS) is a software that:

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Enables you to implement a database withtables, columns, and indexes.
Guarantees the Referential Integrity between rows of various tables.
Updates the indexes automatically.
Interprets an SQL query and combines information from various tables.

RDBMS Terminology:
Before we proceed to explain MySQL database system, lets revise few definitions related to
database.

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Database: A database is a collectionof tables, with related data.
Table: A table is a matrix with data. A table in a database looks like a simple
spreadsheet.
Column: One column (data element) contains data of one and the same kind, for
example the column postcode.
Row: A row (= tuple, entry or record) is a group of related data, for example the data
of one subscription.
Redundancy: Storing data twice, redundantly to make thesystem faster.
Primary Key: A primary key is unique. A key value can not occur twice in one table.
With a key you can find at most one row.
Foreign Key: A foreign key is the linking pin between two tables.
Compound Key: A compound key (composite key) is a key that consists of multiple
columns, because one column is not sufficiently unique.
Index: An index in a database resembles an index atthe back of a book.
Referential Integrity: Referential Integrity makes sure that a foreign key value
always points to an existing row.

MySQL Database:
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Tutorials Point, Simply Easy Learning
MySQL is a fast, easy-to-use RDBMS used being used for many small and big businesses.
MySQL is developed, marketed, and supported by MySQL AB, which is a Swedish company.
MySQL is becoming sopopular because of many good reasons.

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MySQL is released under an open-source license. So you have nothing to pay to use it.
MySQL is a very powerful program in its own right. It handles a large subset of the
functionality of the most expensive and powerful database packages.
MySQL uses a standard form of the well-known SQL data language.
MySQL works on manyoperating systems and with many languages including PHP,
PERL, C, C++, JAVA etc.
MySQL works very quickly and works well even with large data sets.
MySQL is very friendly to PHP, the most appreciated language for web development.
MySQL supports large databases, up to 50 million rows or more in a table. The default
file size limit for a table is 4GB, but you can increase this (if your operatingsystem can
handle it) to a theoretical limit of 8 million terabytes (TB).
MySQL is customizable. The open source GPL license allows programmers to modify the
MySQL software to fit their own specific environments.

Before You Begin:
Before you begin this tutorial you should have a basic knowledge of the information covered in
our PHP and HTML tutorials.
This tutorial focuses heavily on using...