You would need special privilege to create or to delete a MySQL database. So assuming you have access to root user, you can create any database using mysql mysqladmin binary.
Example:
Here is a simple example to create database called TUTORIALS:
[root@host]# mysqladmin -u root -p create TUTORIALS
Enter password:******
This will create a MySQL database TUTORIALS.
Create Database using PHP Script:
PHP uses mysql_query function to create or delete a MySQL database. This function takes two parameters and returns TRUE on success or FALSE on failure.
Syntax:
bool mysql_query( sql, connection );
Parameter Description
sql Required - SQL query to create or delete a MySQL database
connection Optional - if not specified then last opened connection by mysql_connect will be used.