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Q) Explain about Loading JDBC driver?

A)
->In the application point of view JDBC driver is a java class. A java class is stored in the file system as “.class” file, i.e. in secondary memory.
->A java class that is stored in secondary memory can not contribute to the application functionary.
->bringing java class file from secondary memory into primary memory is known as loading a class.
->driver class has to be dynamically loading into the memory.
->in lava.long package a library class “Class” has a static method “forName()”. Using this method we load the JDBC driver dynamically, form secondary memory into primary directories.

Ex:
Class.forName(“oracle.jdbc.driver.OracleDriver”);  //second party provide driver class
        Or
Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”);  //first party provided driver

->when the above method is successfully executed, three things happen in the background.
1) Driver class is loaded from secondary memory into primary memory.
2) Driver class object is created.
3) Driver class object (instance) is registered with driver manager.

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