It will return a connection object or an error object which will be stored in $db. You may be wondering what that wierd :: is. Well, DB is the class for data abstraction and connect is the function. Normally you would see it look like DB->connect(). The reason for the :: is so that we can use the connect function without creating an instance of the class DB. Maybe a little bit different than you are used to, but it has its uses. The :: can also be used to access a function of a base class when you are dealing with inherited classes.
You can see that we passed the connect function what sort of looks like a URL. This is a dsn, or data source name. Here you pass it the database type and other connection information such as username and password. Here is a list of supported database types:mysql -> MySQLpgsql -> PostgreSQLibase -> InterBasemsql -> Mini SQLmssql -> Microsoft SQL Serveroci8 -> Oracle 7/8/8iodbc -> ODBC (Open Database Connectivity)sybase -> SyBaseifx -> Informixfbsql -> FrontBase
The second, optional parameter is whether to use persistent connections or not. Not all databases support persistent connections and the default for this parameter is false.
