Technology Questions

An interface without having any methods and by implementing that interface if our objects will get same ability such type interfaces are called marker interface (or) ability interface (or) tag interface

EIBRCODE

A package is a collection of related PL/SQL objects. The package contains a body and a specification. The package specification has the declaration which is public and can be used in the PL/SQL sub programs inside the package.

The package body holds the implementation of all the PL/SQL objects declared in the specification.

Example of a PL/SQL Package.

CREATE OR REPLACE PACKAGE emp_data AS 

PROCEDURE add_employee (

      ename VARCHAR2,

      job VARCHAR2,

      mgr NUMBER,

      sal NUMBER,

      deptno NUMBER);

END emp_actions;

CREATE OR REPLACE PACKAGE BODY emp_data AS 

PROCEDURE add_employee (

       ename VARCHAR2,

       job VARCHAR2,

       mgr NUMBER,

       sal NUMBER,

       deptno NUMBER) IS

BEGIN

         INSERT INTO emp VALUES (empno_seq.NEXTVAL, ename, job, mgr, SYSDATE, comm, deptno);

END add_employee;

END emp_data;

Advantages of  PL/SQL packages :

Packages are easier for application designing, encapsulating data, additional functionality and better performance. An application has various modules which can be placed in packages and handled easier.

By using
$_SERVER['HTTP_USER_AGENT']
variable.

It enables SQL server to address diverse data sources like OLE DB similarly. It allows Remote server access and has the ability to issue distributed queries, updates, commands and transactions.

The interface org.apache.struts.upload.FormFile is used for the struts file upload application. This interface represents a file that has been uploaded by a client. It is the only interface or class in upload package which is typically referenced directly by a Struts application.

This is not specific to Struts in case of DHTML but the two things that are needed in DHTML page is: first, the form needs to specify an enctype of multipart/form-data and second an <input> form control of type file.

Following are the steps to load file in DHTML:

- Creating a bean

- Writing the ActionClass.

- Mapping the bean in struts-config.xml

- Defining actionmapping

- Developing the DHTML page.