To retrieve and manipulate the data from MySQL database server.

This function requires four parameters to connect to database server.

INSERT, SELECT,UPDATE and DELETE.

MySQLi is extension in PHP scripting language which gives access to the MYSQL database.

Relational Database Management System.

1. The mysqli_affected_rows() function returns the number of affected rows in the previous SELECT, INSERT, UPDATE, REPLACE,or DELETE query.
2. Syntax
mysqli_affected_rows( connection);

1.The mysqli_connect_error() function returns the error description from the last connection error, if any.
2.Syntax
mysqli_connect_error( );

1. The mysqli_fetch_assoc() function fetches a result row as an associative array .
2. Syntax
mysqIi_fetch_assoc(result);

1. A Web database is a database application designed to be managed and accessed through the Internet.
2. In other words, the light databases that support the web applications are also known as Web Databases

(i) In computing, a connection string is a string that specifies information about a data source and the means of connected to it.
(ii) It is passed in code to underlying driver or provider in order to initiate the connection.

EXAMPLES:
(i) SELECT * FROM Customers;
(ii) SELECT CustomerName, City FROM Customers;
(iii) SELECT * FROM Customers WHERE Country='Mexico';
(iv) SELECT * FROM Customers WHERE Country=Germany' AND City='Berlin;
(v) DELETE FROM Customers WHERE CustomerName='Alfreds Futterkiste';

Types of MYSQL Functions in PHP:
(i) Database Connectíons
(ii) Managing Database
(iii) Performing Queries
(iv) Closing Connection

(i) The MySQLi functions allows you to access MYSQL database servers.
(ii) For the MYSQL functions to be available, you must compile PHP with support for the MYSQLi extension.

(i) Mysqli_connect() Function
(ii) Mysqli_close() Function
(iii) Mysqli_query() Function