PROCEDURE VS FUNCTION ORACLE

Differences between Stored Procedures and Functions

• Procedure can return zero or n values whereas function can return one value which is mandatory.
• Procedures can have input/output parameters for it whereas functions can have only input parameters.
• Procedure allows select as well as DML statement in it whereas function allows only select statement in it.
• Functions can be called from procedure whereas procedures cannot be called from function.
• Exception can be handled by try-catch block in a procedure whereas try-catch block cannot be used in afunction.
• We can go for transaction management in procedure whereas we can't go in function.
• Procedures can not be utilized in a select statement whereas function can be embedded in a select statement.

In depth

Stored Procedure 

A Stored Procedure is a program (or procedure) which is physically stored within a database. They are usually written in a proprietary database language like PL/SQL for Oracle database or PL/PgSQL for PostgreSQL. The advantage of a stored procedure is that when it is run, in response to a user request, it is run directly by the database engine, which usually runs on a separate database server. As such, it has direct access to the data it needs to manipulate and only needs to send its results back to the user, doing away with the overhead of communicating large amounts of data back and forth.

User-defined Function

A user-defined function is a routine that encapsulates useful logic for use in other queries. While views are limited to a single SELECT statement, user-defined functions can have multiple SELECT statements and provide more powerful logic than is possible with views.
User defined functions have three main categories:

1. Scalar-valued function - returns a scalar value such as an integer or a timestamp. Can be used as column name in queries.
2. Inline function - can contain a single SELECT statement.
3. Table-valued function - can contain any number of statements that populate the table variable to be returned. They become handy when you need to re

CREATING CAB FILES IN .NET

Imports System
Imports System.IO
Imports System.Text
Imports Microsoft.Deployment.Compression.Cab
Public Class Test

    Public Shared Sub Main()
        Dim path As String = "c:\Newfolder\MyTest.txt"

        ' Delete the file if it exists.
        If File.Exists(path) Then
            File.Delete(path)
        End If

        'Create the file.
        Dim fs As FileStream = File.Create(path)

        AddText(fs, "This is some text")
        AddText(fs, "This is some more text,")
        AddText(fs, Environment.NewLine & "and this is on a new line")
        AddText(fs, Environment.NewLine & Environment.NewLine)
        AddText(fs, "The following is a subset of characters:" & Environment.NewLine)

        Dim i As Integer

        For i = 1 To 120
            AddText(fs, Convert.ToChar(i).ToString())

        Next

        fs.Close()

        Dim __cab As CabInfo
        Dim list As New List(Of String)
        list.Add("c:\Newfolder\MyTest.txt")
        __cab = New CabInfo("c:\Newfolder\cab1.cab")
        __cab.PackFiles(Nothing, list, Nothing)
        ''Open the stream and read it back.
        'fs = File.OpenRead(path)
        'Dim b(1024) As Byte
        'Dim temp As UTF8Encoding = New UTF8Encoding(True)

        'Do While fs.Read(b, 0, b.Length) > 0
        '    Console.WriteLine(temp.GetString(b))
        'Loop

        'fs.Close()
    End Sub

    Private Shared Sub AddText(ByVal fs As FileStream, ByVal value As String)
        Dim info As Byte() = New UTF8Encoding(True).GetBytes(value)
        fs.Write(info, 0, info.Length)
    End Sub
End Class

Dynamically Change CSS on Button Click in ASP.NET

This article will explain on how css can be changed dynamically on button click in asp.net

Introduction

Hello friends, in this article we will see how to change the CSS of asp.net application dynamically.

In this article, button is being used to change the CSS using the Button Click event.

Objective

There are lots of time we want to change the background dynamically and also the look and feel of the website and you regret using Themes because it only works for asp.net controls and not to HTML Controls.Hence we can use CSS. For simplicity asp.net controls are used in this article,however HTML controls can be used as well.

Using the code

We have 1 label and 2 buttons, The first button will change the background of the webpage to maroon color and font family and the look of the label as well and the second button will change the background color to yellow and the font and the labels look and feel as per CSS.

To work around we have to implement a default look and feel,hence for that i have kept the background color to aqua.so when the page will load for the first time it will have the look and feel of the default css and on button clicks it will change the css and apply the changes as per css rule.

Now to change the CSS dynamically on button click we will use the command argument value given to the button in HTML mark up.

The command argument is the name of the css with extension of the css as well.

In all the css i have a common class .label so that i can also change the look and the feel of the label as well as per the changing the css.

For this i have assigned .label class to the label control.

Make a note that the default.css should have the .label class so that you can apply the changes to the label.

************Using the code and understanding the code*************************

 id="lnkCSS" href="css/Default.css" runat="server" rel="stylesheet" type="text/css" /> 

The above line if you check i have set the runat = server mode to the link so that i can get this link on code behind to change its properties on code behind.

Block of code should be set style as "Code" like below.

// HTML Mark Up

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Dymaic Change of Css.aspx.cs" Inherits="Dymaic_Change_of_Css" %>

 xmlns="http://www.w3.org/1999/xhtml">
 runat="server">
    
     id="lnkCSS" href="css/Default.css" runat="server" rel="stylesheet" type="text/css" />


    

 id="form1" runat="server">
    



     ID="lblseeEffect" runat="server" Text="This is a Label" CssClass="label">
 />
 />
     ID="btnCss1" runat="server" CommandArgument="Brown.css" 
            Text="Apply Brown Theme" onclick="btnCss1_Click" />          
     ID="btnCss2" runat="server" CommandArgument="Yellow.css" 
            Text="Apply Yellow Theme" onclick="btnCss2_Click" />
    

   
   

//Default.css

body {
        background-color:Aqua;
        font-family:@Adobe Gothic Std B;
        font-size:15pt;
}
.label{
    font-weight:bold;
    color:Red;
}

//Brown.css

body {
        background-color:Maroon;
        font-family:@GulimChe;
        }
.label{
    font-weight:bold;
    color:Yellow;
    font-size:20pt;
}

Yellow.css

body {
        background-color:Yellow;
        font-family:Adobe Caslon Pro Bold;
}
.label{
        color:Maroon;
        font-size:15pt;
        }

//Code behind

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
public partial class Dymaic_Change_of_Css : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void btnCss1_Click(object sender, EventArgs e)
    {
        lnkCSS.Attributes["href"] = "~/css/" + (sender as Button).CommandArgument; // this will change the css as per the command agruement given in the HTML mark up
    }
    protected void btnCss2_Click(object sender, EventArgs e)
    {
        lnkCSS.Attributes["href"] = "~/css/" + (sender as Button).CommandArgument;// this will change the css as per the command agruement given in the HTML mark up

    }
}