DriverManager-It is a class of java.sql package that controls a set of JDBC drivers. Each driver has to be register with this class.
getConnection()-This method establishes a connection to specified database url. This method takes a string containing a URL.
Class.forName()-This method is static. It attempts to load the class and returns class instance and takes string type value (driver) after that matches class with given string.
DSN-It represents an ODBC connection to a particular database server.
sun.jdbc.odbc.JdbcOdbcDriver- This is the class where Type 1 Driver is implemented.
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