Technical Tips and Techniques by Ravindra Gullapalli

Rename files in bulk through command prompt in windows

noreply@blogger.com (Ravindra Gullapalli) — Mon, 06 Feb 2012 07:27:00 +0000

This could be a peculiar requirement for many of us but some times it may require to change the file extensions in bulk. For example, you want to rename .txt files to .bat files. As usual googled for softwared for this and there are many softwares available. Tried few but I didn't feel much comfortable with any of those.

Windows has provided a facility to do this task very easily.

To to command prompt and go to the directory in which you want to change file extensions.and use simple command rename *.txt *.bat OR ren *.txt *.bat. Thats it. All your text files will become batch files.

I've to try the renaming in the file name itself. If you know, you can post here.

Isn't that simple? Why to download "MBs" of softwares for that :) Give a try.

Send Ctrl+Alt+Del to your RDP Machine

noreply@blogger.com (Ravindra Gullapalli) — Sat, 04 Feb 2012 10:32:00 +0000

Ctrl+Alt+Del is an unique feature which windows has and when your computer hangs, you can use this key combination, go to task manager and then kill the un-responsive processes.

But if you are working on a remote computer using RDP (Remote Desktop) and if that computer hangs, how to send this key combination? Is there any solution for this?

The answer is YES. You can use Ctrl+Alt+End which will do this for you on a remote computer.

JList - Prevent Item Selection when you have only One Item

noreply@blogger.com (Ravindra Gullapalli) — Thu, 02 Feb 2012 02:57:00 +0000

Lets take a scenario where you have only one item in JList. By default if you click on empty space of JList, the first item will be selected. To prevent that, you have to add mouse listener and then have to handle that. Here is an example.

public class JListOperations extends javax.swing.JFrame {
    private static final long serialVersionUID = 1L;
    private javax.swing.JScrollPane jsp = null;
    private javax.swing.JList<java.lang.String> jl = null;
    public JListOperations(){
        super();    
    }
    public void initialiseComponents(){
        jl = new javax.swing.JList<java.lang.String>(new java.lang.String[]{"Item 1"});
        /*
         * Add mouse listener which checks if the mouse click point is on the item. If not deselect the item  
         */
        jl.addMouseListener(new java.awt.event.MouseAdapter(){
            public void mouseClicked(java.awt.event.MouseEvent mouseEvent){
                if (!jl.getCellBounds(jl.getSelectedIndex(), jl.getSelectedIndex()).contains(mouseEvent.getPoint())){
                    jl.removeSelectionInterval(jl.getSelectedIndex(), jl.getSelectedIndex());
                }
                java.lang.System.out.println(jl.getSelectedIndex());
            }
        });
        jsp = new javax.swing.JScrollPane(jl);
        getContentPane().add(jsp);
        setDefaultCloseOperation(EXIT_ON_CLOSE);
    }
    public static void main(java.lang.String args[]){
        JListOperations jlopFrame = new JListOperations();
        jlopFrame.initialiseComponents();
        jlopFrame.pack();
        jlopFrame.setVisible(true);
    }
}

Interesting lastModified() behaviour

noreply@blogger.com (Ravindra Gullapalli) — Tue, 31 Jan 2012 00:44:00 +0000

The method lastModified() in java.io.File, which gives the milli seconds from 01-Jan-1970 till the file modified date is behaving differently in different situations.

When I checked it in my IDE (Eclipse Indigo), it was giving properly but when I make a jar file out of it and execute it directly, it was giving 0.

After lot of RnD :), I found that the issue is with the rights. You should run the jar file (javaw.exe) as administrator. It is not sufficient even if you are in administrator group of the system.

Clear Login Name list SQL Server Management Studio

noreply@blogger.com (Ravindra Gullapalli) — Mon, 30 Jan 2012 03:51:00 +0000

If you want to clear the login name list which comes in SQL Server Management Studio 2008, go to

C:\Users\%username%\AppData\Roaming\Microsoft\Microsoft SQL Server\100\Tools\Shell\

and delete SqlStudio.bin

Remember, this action clears Server list too.

This works perfectly in Vista. I think in Windows 7 too. For other operating systems and SQL Server versions, you can have a look at this post.

Table Size Calculations in SQL Server

noreply@blogger.com (Ravindra Gullapalli) — Sat, 21 Jan 2012 08:15:00 +0000

These queries are very much useful to find different lengths of different objects SQL Server Database

To know row length of a table

SELECT OBJECT_NAME (sc.[id]) tablename
, COUNT (1) nr_columns
, SUM (sc.length) maxrowlength
FROM syscolumns sc
join sysobjects so
on sc.[id] = so.[id]
WHERE so.xtype = 'U'
GROUP BY OBJECT_NAME (sc.[id])
ORDER BY SUM (sc.length) desc

To know field length of a table

select MAX(DATALENGTH([Column Name])) from [TableName]

To know table wise, field wise length

select
sys.objects.[name],
sys.objects.[object_id],
count(sys.columns.[name]) As ColumnCount,
sum(sys.columns.max_length) As MaxLength
from
sys.objects
inner join sys.columns on sys.objects.object_id = sys.columns.object_id
where
[type] = 'U'
group by
sys.objects.[name],
sys.objects.[object_id]
order by MaxLength desc

To know space occupied by the database

Sp_spaceused

Clear vtiger CRM Demo Data

noreply@blogger.com (Ravindra Gullapalli) — Sat, 21 Jan 2012 08:01:00 +0000

If you configure vtiger CRM with demo data and after that if you do not want to have demo data, just run this command in mysql vtiger database.

update vtiger_crmentity set deleted = 1

MySQL Service Start Error 1067 : Service terminated unexpectedly

noreply@blogger.com (Ravindra Gullapalli) — Fri, 20 Jan 2012 10:57:00 +0000

I solved it by specifying the defaults file path. If you already have a MySQL windows service named "MySql", first remove it with

mysqld --remove MySql

Then re-install the service with a defaults-file option as follows

mysqld --install <service name> --defaults-file=[full path of "my.ini" file]

For Eg: mysqld --install MySql --defaults-file=D:\MySQL\my.ini

Now start the service.

I hope it helps.

Add multiple files and folders in VSS 2005

noreply@blogger.com (Ravindra Gullapalli) — Mon, 16 Jan 2012 10:32:00 +0000

In Microsoft Visual Source Safe 6.0, there was an option to add multiple files and folders along with sub folders which is missing in Visual Source Safe 2005.

But we can add the folders along with sub folders and files with a small trick.
While adding a folder, instead of doing (Ctrl + A), Press shift and click on "Add Files" button.

This gives you the "Old Add Files Dialog" in which there is an option to add sub folders / files.

Once you select the folder to be added into VSS and click on "Add" button, it gives a "Comments" dialogue, where you can find a check box "Recursive". Choose that if you want to add sub folders and files.

Shift + Ctrl + A won't work. Similarly Shift + Drag drop also won't work.

Those who hate to use mouse, you have to use your mouse. There is no alternative. :)

Avoid multiple clicks to open combo box in DataGridView

noreply@blogger.com (Ravindra Gullapalli) — Sat, 07 Jan 2012 06:50:00 +0000

If you add a Combobox in DataGridView, you have to click twice on that combo box to access that. Here are three different ways to open the combo box.

Private Sub [DataGridView Object]_CellClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles [DataGridView Object].CellClick
If e.ColumnIndex = 4 Then
'[DataGridView Object].BeginEdit(True)
'[DataGridView Object].EditMode = DataGridViewEditMode.EditOnEnter
System.Windows.Forms.SendKeys.SendWait("{F4}")
End If
End Sub

I prefer the SendKeys option as it accesses the combo box as well as it opens that so that we can see the options available in that.

Using JOIN in UPDATE Query in SQL Server

noreply@blogger.com (Ravindra Gullapalli) — Sat, 07 Jan 2012 06:28:00 +0000

Here is an example where you can use joins in UPDATE queries like you do in SELECT.

UPDATE Table1 SET Column1 = T2.Column1[, Column2 = T2.Column2 ...] FROM Table1 T1 INNER JOIN Table2 T2 ON [Join Condition] WHERE [Update Query condition]

Detailed explanation is available at Microsoft website

Cross Browser Compatibility for ASP.NET Applications

noreply@blogger.com (Ravindra Gullapalli) — Wed, 23 Nov 2011 09:58:00 +0000

When we design web applications we generally need to take care about cross browser compatibility. In ASP.NET applications this is taken care for many components but still some components for example, asp:Menu do not won't honour cross browser compatibility.

To handle this situation, we have to add a new component to the ASP.NET application.

Right click on the ASP.NET application and add a ASP.NET folder called App_Browsers.

Right click on that folder, Add New Item and add Browser file and name the file as NonIE.browser

Put the following content in that.

<browsers>
<browser refID="mozilla">
<controlAdapters>
<adapter controlType="System.Web.UI.WebControls.Menu" adapterType="" />
</controlAdapters>
</browser>
</browsers>

While publishing the application, we have to publish App_Browsers.dll file along with App_Code.dll file and other files. Do not copy __browserCapabilitiesCompiler.compiled file. If you copy the compiled file, the cross browser compatibility won't work.

WebServices File Not Found Issue

noreply@blogger.com (Ravindra Gullapalli) — Fri, 04 Nov 2011 14:05:00 +0000

Some times in ASP.NET web services, even if the web pages are working properly, you may get a 404 (File Not Found) error while browsing web services.

To avoid this error, check the Managed Pipeline Mode of the Application Pool to which your web site is attached. If it is Classic, change it to Integrated. If it is Integrated, change it to Classic.

To change the Managed Pipeline Mode, Right click on the Application Pool and go to Basic Settings

Try browsing your web service and it should work now.

Display number in Indian (Lakh) Format in Crystal Report

noreply@blogger.com (Ravindra Gullapalli) — Fri, 30 Sep 2011 13:09:00 +0000

If you want to display a number in Indian (Lakh) format in crystal report, use the following formula.

CStr([Number to be displayed], "##,##,##,###.##")

Hope this helps.

Display first record field value in Crystal Report Footer

noreply@blogger.com (Ravindra Gullapalli) — Tue, 27 Sep 2011 10:08:00 +0000

Let us consider you have set of 5 records with 3 columns. In this, lets think that in the third column only the first record has the value and the other two records do not.

Now, if you want to display that value in footer, you have to do some indirect approach because by the time you reach the footer, all records were read and you will get only the last record value.

To achieve this, just think logically and the answer will be with you.

There is a function called NthLargest which will give the largest value for the given column.Now as the value in other records is blank, it will give you the first record value.

Just create a formula @F1 and in that use the function NthLargest(1, {Command.[Field Name]}). Use that formula in the report and your problem will be solved.

Hope this helps.

Get month name for month number in SQL Server

noreply@blogger.com (Ravindra Gullapalli) — Sat, 24 Sep 2011 11:31:00 +0000

You can use this query to get the name of the month for the given number of month in SQL Server

SELECT DATENAME(MONTH, CAST(CAST(YEAR(GETDATE()) AS VARCHAR) + '-' + CAST([Month Number] AS VARCHAR) + '-01' AS DATETIME)) AS MonthName

Restore a specific table from another database table using queries in SQL Server

noreply@blogger.com (Ravindra Gullapalli) — Tue, 20 Sep 2011 12:44:00 +0000

Note: Please backup the table data before running this USP. Run this USP at your own risk.

ALTER PROCEDURE [dbo].[usp_RestoreTabData]
    @SourceDBName VARCHAR(MAX),
    @TargetDBName VARCHAR(MAX),
    @TableNameToRestore VARCHAR(MAX)
AS
BEGIN
    BEGIN TRY
        BEGIN TRANSACTION
        DECLARE @DeleteQuery VARCHAR(MAX)
        DECLARE @UpdateQuery VARCHAR(MAX)
        DECLARE @TableName VARCHAR(MAX)
        DECLARE @TableObjectId INTEGER
        --    Get the list of tables
        DECLARE TabCursor CURSOR FOR SELECT object_id, name FROM sys.tables WHERE name = @TableNameToRestore
        OPEN TabCursor
        --    Iterate through all the tables
        FETCH NEXT FROM TabCursor INTO @TableObjectId, @TableName
        WHILE @@FETCH_STATUS = 0
            BEGIN
                --    Start preparing update query
                SET @UpdateQuery = 'UPDATE OuterTab SET '
                --    Get list of primary key columns of the table
                --DECLARE @PKSPCall VARCHAR(MAX)
                --SET @PKSPCall = 'EXEC sp_pkeys ' & @TableName
                --SELECT * INTO #PKTable FROM OPENROWSET('SQLNCLI', 'Server=(local)\SDBSPROD;Trusted_Connection=yes;', 'EXEC sp_pkeys FADAccountingPeriod')
                --DECLARE PrimaryKeyCursor CURSOR FOR SELECT * FROM #PKTable
                DECLARE PrimaryKeyCursor CURSOR FOR SELECT   COL_NAME(ic.OBJECT_ID,ic.column_id) AS ColumnName FROM    sys.indexes AS i INNER JOIN          sys.index_columns AS ic ON i.OBJECT_ID = ic.OBJECT_ID                                 AND i.index_id = ic.index_id WHERE   i.is_primary_key = 1 AND IC.Object_Id = @TableObjectId
                --DROP TABLE #PKTable
                DECLARE @PrimaryKeyCol VARCHAR(MAX)
                OPEN PrimaryKeyCursor
                --    Prepare primary key condition string. This string should be prepared in the format
                --    [Target db].dbo.[target table].column name = [source db].dbo.[source table].column name
                --    As this is a co-related sub query, it can be shortened to column name = [source db].dbo.[source table].column name
                FETCH NEXT FROM PrimaryKeyCursor INTO @PrimaryKeyCol
                DECLARE @WhereClause VARCHAR(MAX)
                SET @WhereClause = ' Licensee = OuterTab.Licensee '
                WHILE @@FETCH_STATUS = 0
                    BEGIN
                        --    Licensee is hardcoded above
                        IF @PrimaryKeyCol <> 'Licensee'
                            BEGIN
                                SET @WhereClause = @WhereClause + ' AND ' + @PrimaryKeyCol + ' = OuterTab.' + @PrimaryKeyCol
                            END
                        FETCH NEXT FROM PrimaryKeyCursor INTO @PrimaryKeyCol
                    END
                CLOSE PrimaryKeyCursor
                DEALLOCATE PrimaryKeyCursor
                --    Ignore AND in the beginning of where clause
                --    SET @WhereClause = SUBSTRING(@WhereClause, 4, LEN(@WhereClause) - 4)
                --    Get list of columns in the table
                DECLARE ColCursor CURSOR FOR SELECT name from sys.columns WHERE object_id = @TableObjectId
                DECLARE @ColumnName VARCHAR(MAX)
                OPEN ColCursor
                --    Iterate through all the columns and prepare the query
                FETCH NEXT FROM ColCursor INTO @ColumnName
                WHILE @@FETCH_STATUS = 0
                    BEGIN
                        SET @UpdateQuery = @UpdateQuery + @ColumnName + '=(SELECT ' + @ColumnName + ' FROM ' + @SourceDBName + '.dbo.' + @TableName + ' WHERE ' + @WhereClause + '),'
                        FETCH NEXT FROM ColCursor INTO @ColumnName
                    END
                CLOSE ColCursor
                DEALLOCATE ColCursor
                SET @UpdateQuery = SUBSTRING(@UpdateQuery, 0, LEN(@UpdateQuery)) + ' FROM ' + @TableName + ' AS OuterTab WHERE Licensee = 1001'
                PRINT 'Copy the below queries, verify and execute'
                PRINT @UpdateQuery
                SET @UpdateQuery = ''
                --Start preparing delete query
                SET @DeleteQuery = 'DELETE FROM ' + @TableNameToRestore + ' WHERE Licensee = 1001 AND 0 = (SELECT COUNT(*) FROM ' + @SourceDBName + '.dbo.' + @TableNameToRestore + ' WHERE ' + REPLACE(@WhereClause, 'OuterTab', @TableNameToRestore) + ')'
                PRINT @DeleteQuery
                SET @DeleteQuery = ''
                FETCH NEXT FROM TabCursor INTO @TableObjectId, @TableName
            END
        COMMIT
        CLOSE TabCursor
        DEALLOCATE TabCursor
    END TRY
    BEGIN CATCH
        --    Both statements will work to print error number
        PRINT 'Error : ' + CONVERT(VARCHAR, @@ERROR)
        --    PRINT 'Error : ' + ltrim(str(error_number()))
        PRINT 'Description : ' + ERROR_MESSAGE()
        --    Ignore errors if the cursors does not exist
        BEGIN TRY
            CLOSE ColCursor
            DEALLOCATE ColCursor
        END TRY
        BEGIN CATCH
            --    Both statements will work to print error number
            PRINT 'Error : ' + CONVERT(VARCHAR, @@ERROR)
            --    PRINT 'Error : ' + ltrim(str(error_number()))
            PRINT 'Description : ' + ERROR_MESSAGE()
        END CATCH
        BEGIN TRY
            CLOSE PrimaryKeyCursor
            DEALLOCATE PrimaryKeyCursor
        END TRY
        BEGIN CATCH
            --    Both statements will work to print error number
            PRINT 'Error : ' + CONVERT(VARCHAR, @@ERROR)
            --    PRINT 'Error : ' + ltrim(str(error_number()))
            PRINT 'Description : ' + ERROR_MESSAGE()
        END CATCH
        BEGIN TRY
            CLOSE TabCursor
            DEALLOCATE TabCursor
        END TRY
        BEGIN CATCH
            --    Both statements will work to print error number
            PRINT 'Error : ' + CONVERT(VARCHAR, @@ERROR)
            --    PRINT 'Error : ' + ltrim(str(error_number()))
            PRINT 'Description : ' + ERROR_MESSAGE()
        END CATCH
        ROLLBACK
    END CATCH
END

Log required information from your Web requests using a HTTP Module in .Net

noreply@blogger.com (Ravindra Gullapalli) — Tue, 20 Sep 2011 12:21:00 +0000

Some times in the web applications, we require logging of specific information which will be available in the requests. We can achieve in .NET by using a HttpModule. Here is an example given for that with VB Coading.

web.config Entries (Add any one or both of the following entries depending on the requirement)

If you want to add inside <system.web> tag then add the following

If you want to add inside <system.webServer> tag then add the following

</modules>

The class

Imports Microsoft.VisualBasic
''' <summary>
''' Responds to each request of web site / web service page and writes the request time, session id and request URL in log file.
''' </summary>
''' <remarks>This will create a folder RequestLogs if not present and it will create a date wise log</remarks>
Public Class MyWebFilterModule
    Implements System.Web.IHttpModule, System.Web.SessionState.IRequiresSessionState, System.Web.SessionState.IReadOnlySessionState
    ''' <summary>
    ''' Hashtable to hold the request
    ''' </summary>
    ''' <remarks></remarks>
    Private Shared RequestHash As System.Collections.Hashtable = New System.Collections.Hashtable()
    Public Sub New()
    End Sub
    ''' <summary>
    ''' Provides HTTP module name
    ''' </summary>
    ''' <value></value>
    ''' <returns>HTTP module name</returns>
    ''' <remarks></remarks>
    Public ReadOnly Property ModuleName() As String
        Get
            Return "MyWebFilterModule"
        End Get
    End Property
    ''' <summary>
    ''' In the Init function, register for HttpApplication events by adding your handlers.
    ''' </summary>
    ''' <param name="application"></param>
    ''' <remarks></remarks>
    Public Sub Init(ByVal application As HttpApplication) _
            Implements IHttpModule.Init
        AddHandler application.PreRequestHandlerExecute, _
            AddressOf Me.Application_PreRequestHandlerExecute
        AddHandler application.EndRequest, _
            AddressOf Me.Application_EndRequest
    End Sub
    ''' <summary>
    ''' Logs before processing the request
    ''' </summary>
    ''' <param name="sender"></param>
    ''' <param name="e"></param>
    ''' <remarks></remarks>
    Protected Sub Application_PreRequestHandlerExecute(ByVal sender As Object, ByVal e As EventArgs)
        Dim RequestHeaderHash As System.Collections.Hashtable = New System.Collections.Hashtable()
        ' Create HttpApplication and HttpContext objects to access
        ' request and response properties.
        Dim application As HttpApplication = DirectCast(sender, _
            HttpApplication)
        '   Log only aspx and asmx pages
        If IsToProcessRequest(application) Then
            Dim context As HttpContext = application.Context
            Dim SessionID As System.String = "NA"
            If context.Session IsNot Nothing Then
                SessionID = context.Session.SessionID
            End If
            '   Keep session in request header to use in end request
            RequestHeaderHash.Add("SessionID", SessionID)
            RequestHeaderHash.Add("RequestNumber", RequestHash.Count + 1)
            Dim CurrentTime As System.DateTime = System.DateTime.Now
            RequestHeaderHash.Add("RST", CurrentTime) '   Add request start time to request header to get the difference when the request ends
            Try
                '   Create request logs directory
                If Not System.IO.Directory.Exists(context.Server.MapPath("~/RequestLogs")) Then
                    System.IO.Directory.CreateDirectory(context.Server.MapPath("~/RequestLogs"))
                End If
                '   Check if it is web service to provide special treatment
                Dim IsWebService As Boolean = GetFileExtensionInRequest(application).Equals(".asmx")
                '   Check for file existance
                If Not System.IO.File.Exists(context.Server.MapPath("~/RequestLogs/" & CurrentTime.ToString("dd_MMM_yyyy") & ".txt")) Then
                    '   Create file and print headings
                    System.IO.File.AppendAllText(context.Server.MapPath("~/RequestLogs/" & CurrentTime.ToString("dd_MMM_yyyy") & ".txt"), "RequestNumber" & vbTab & "Start Time" & vbTab & "End Time" & vbTab & "Time Taken" & vbTab & IIf(IsWebService, "", "Session ID" & vbTab) & "URL" & vbTab & IIf(IsWebService, "Method" & vbTab, "") & IIf(IsWebService, "Parameters" & vbTab, "") & vbCrLf)
                End If
                '   For SOAP requests (web service calls), get the method and param names
                Dim ParameterString As StringBuilder = New StringBuilder()
                Dim SOAPMethodName As String = ""
                If IsWebService Then
                    '   Get the input stream
                    Dim HttpInputStream As System.IO.Stream = context.Request.InputStream
                    '   Get the current position to reset the position at the end for request processing
                    Dim HttpStreamPosition As Long = HttpInputStream.Position
                    '   Load the stream into xml document
                    Dim SOAPXmlDocument As System.Xml.XmlDocument = New System.Xml.XmlDocument()
                    SOAPXmlDocument.Load(HttpInputStream)
                    '   Get the actual body element and get the method name and parameter names
                    Dim SOAPBodyNode As System.Xml.XmlNode = SOAPXmlDocument.GetElementsByTagName("soap:Body")(0)
                    If SOAPBodyNode IsNot Nothing Then
                        Dim SOAPBodyNodes As IEnumerator = SOAPBodyNode.GetEnumerator
                        While SOAPBodyNodes.MoveNext
                            Dim SOAPMethodNode As System.Xml.XmlNode = CType(SOAPBodyNodes.Current, System.Xml.XmlNode)
                            SOAPMethodName = SOAPMethodNode.Name
                            Dim SOAPMethodNodes As IEnumerator = SOAPMethodNode.GetEnumerator
                            While SOAPMethodNodes.MoveNext
                                Dim SOAPParameterNode As System.Xml.XmlNode = CType(SOAPMethodNodes.Current, System.Xml.XmlNode)
                                ParameterString.Append("[ParameterName : " & SOAPParameterNode.Name & ", ParameterValue : " & SOAPParameterNode.InnerText & "]")
                            End While
                        End While
                    End If
                    '   Reset the stream position for further request processing
                    HttpInputStream.Position = HttpStreamPosition
                End If
                RequestHash.Add(context.Request, RequestHeaderHash)
                '   Log the request info
                System.IO.File.AppendAllText(context.Server.MapPath("~/RequestLogs/" & CurrentTime.ToString("dd_MMM_yyyy") & ".txt"), RequestHeaderHash("RequestNumber") & vbTab & CurrentTime.ToString("dd-MMM-yyyy HH:mm:ss") & vbTab & " " & vbTab & " " & vbTab & IIf(IsWebService, "", SessionID & vbTab) & context.Request.RawUrl & vbTab & IIf(IsWebService, SOAPMethodName & vbTab, "") & IIf(IsWebService, ParameterString.ToString() & vbTab, "") & vbCrLf)
            Catch ex As Exception
                '   Ignore file lock exception
            End Try
        End If
    End Sub
    ''' <summary>
    ''' Logs when the request ends
    ''' </summary>
    ''' <param name="sender"></param>
    ''' <param name="e"></param>
    ''' <remarks></remarks>
    Protected Sub Application_EndRequest(ByVal sender As Object, ByVal e As EventArgs)
        Dim application As HttpApplication = DirectCast(sender, _
                    HttpApplication)
        '   Log only aspx and asmx pages
        If IsToProcessRequest(application) Then
            Dim RequestHeaderHash As System.Collections.Hashtable = CType(RequestHash(application.Context.Request), System.Collections.Hashtable)
            Dim context As HttpContext = application.Context
            '   Session id is also important here to check whether a new session is created / existing session is used
            Dim SessionID As System.String = "NA"
            If RequestHeaderHash IsNot Nothing AndAlso RequestHeaderHash("SessionID") IsNot Nothing Then
                SessionID = RequestHeaderHash("SessionID")
            End If
            Dim CurrentTime As System.DateTime = System.DateTime.Now
            Dim TimeDifference As System.DateTime
            If RequestHeaderHash IsNot Nothing AndAlso RequestHeaderHash("RST") IsNot Nothing Then
                TimeDifference = New System.DateTime(CurrentTime.Ticks - CType(RequestHeaderHash("RST"), System.DateTime).Ticks)
            End If
            Dim IsWebService As Boolean = GetFileExtensionInRequest(application).Equals(".asmx")
            Try
                System.IO.File.AppendAllText(context.Server.MapPath("~/RequestLogs/" & CurrentTime.ToString("dd_MMM_yyyy") & ".txt"), RequestHeaderHash("RequestNumber") & vbTab & " " & vbTab & CurrentTime.ToString("dd-MMM-yyyy HH:mm:ss") & vbTab & TimeDifference.ToString("HH:mm:ss") & vbTab & IIf(IsWebService, "", SessionID & vbTab) & " " & vbTab & IIf(IsWebService, " " & vbTab, "") & IIf(IsWebService, " " & vbTab, "") & vbCrLf)
            Catch ex As Exception
                '   Ignore file lock exception
            End Try
        End If
    End Sub
    ''' <summary>
    ''' Dispose the object
    ''' </summary>
    ''' <remarks></remarks>
    Public Sub Dispose() Implements System.Web.IHttpModule.Dispose
    End Sub
    ''' <summary>
    ''' Controls the request logging. This is to log only the requests for aspx and asmx pages
    ''' </summary>
    ''' <param name="application"></param>
    ''' <returns>True if the page is aspx or asmx page and False otherwise</returns>
    ''' <remarks></remarks>
    Private Function IsToProcessRequest(ByVal application As HttpApplication) As Boolean
        '   Log only aspx and asmx pages
        Dim FileExtension As String = GetFileExtensionInRequest(application)
        Return FileExtension.Equals(".aspx") OrElse FileExtension.Equals(".asmx")
    End Function
    ''' <summary>
    ''' Provides file name extension in the request URL
    ''' </summary>
    ''' <param name="application"></param>
    ''' <returns></returns>
    ''' <remarks></remarks>
    Private Function GetFileExtensionInRequest(ByVal application As HttpApplication) As String
        Dim context As HttpContext = application.Context
        Dim filePath As String = context.Request.FilePath
        Return VirtualPathUtility.GetExtension(filePath)
    End Function
End Class

Add Text at the Cursor Position in HTMLEditor AjaxControlToolkit

noreply@blogger.com (Ravindra Gullapalli) — Tue, 20 Sep 2011 11:58:00 +0000

If you want to add text at the current cursor (caret) position in HTMLEditor AjaxControlToolkit in ASP.NET, use the following javascript code in your page

function insertTextInHTMLEditorAtCursor(textToInsert){
    // Get the editor control
    var editorControl = $get("<%=[HTMLEditor ID].ClientID%>").control;
    // Get EditPanel
    var editPanel = editorControl.get_editPanel();
    // Add the text if the active mode is 'Design' (AjaxControlToolkit.HTMLEditor.ActiveModeType.Design) which is 0
    if (editPanel.get_activeMode() == 0) {
        // Get the DesignPanel object
        var designPanel = editPanel.get_activePanel();
        // Save content to support 'Undo'
        designPanel._saveContent();
        // Insert some text at current cursor position
        designPanel.insertHTML(textToInsert);
        // Notify Editor about content changed and update toolbars linked to the edit panel
        setTimeout(function () { designPanel.onContentChanged(); editPanel.updateToolbar(); }, 0);
        // Focus in design panel
        designPanel.focusEditor();
    }
}

Additional NULL columns in DB2 select query

noreply@blogger.com (Ravindra Gullapalli) — Sat, 17 Sep 2011 13:11:00 +0000

Some times there might be a necessity to select additional NULL values along with the columns in a table in select queries. Here I'm giving the procedure in two databases.

In SQL Server

SELECT [Col 1], [Col 2], NULL AS [Col 3], ... [Col n] FROM [Table]

In DB2

It is not that simple to retrieve NULL values in additional columns like in SQL Server.
You have to write the query by keeping the target data type of the NULL column in mind
The process is here

Please post comments if you know the process in ORACLE / MySQL

Retrieve Referential Constraint Info of Related Tables in SQL Server

noreply@blogger.com (Ravindra Gullapalli) — Thu, 15 Sep 2011 13:10:00 +0000

Use this query to retrieve the related tables information and the related columns information for a given table in Microsoft SQL Server 2008. Didn't checked in other versions. Please comment if this same query works with older versions too.

SELECT
PK_Table = PK.TABLE_NAME,
PK_Column = PT.COLUMN_NAME,
PK_Ordinal = PT.ORDINAL_POSITION,
FK_Table = FK.TABLE_NAME,
FK_Column = CU.COLUMN_NAME,
FK_Ordinal = CU.ORDINAL_POSITION,
Constraint_Name = C.CONSTRAINT_NAME
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS C
INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS FK ON C.CONSTRAINT_NAME = FK.CONSTRAINT_NAME
INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS PK ON C.UNIQUE_CONSTRAINT_NAME = PK.CONSTRAINT_NAME
INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE CU ON C.CONSTRAINT_NAME = CU.CONSTRAINT_NAME
INNER JOIN (
SELECT i1.TABLE_NAME, i2.COLUMN_NAME, i2.ORDINAL_POSITION
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS i1
INNER JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE i2 ON i1.CONSTRAINT_NAME = i2.CONSTRAINT_NAME
WHERE i1.CONSTRAINT_TYPE = 'PRIMARY KEY'
) PT ON PT.TABLE_NAME = PK.TABLE_NAME AND PT.ORDINAL_POSITION = CU.ORDINAL_POSITION

WHERE PK.TABLE_NAME = '[Table Name]'
ORDER BY PK_Table, FK_Table, PK_Ordinal

Just comment WHERE PK.TABLE_NAME = '[Table Name]' to get all related tables

requestFocus in Swings

noreply@blogger.com (Ravindra Gullapalli) — Mon, 12 Sep 2011 01:21:00 +0000

In swings Component, there is a method called requestFocus which sets the focus in the specified component. If we want to set the focus into a control when the form is opened, it is not sufficient to write the line [Control instance].requestFocus() in the constructor.

You need to add the following code snippet to achieve that result.

javax.swing.SwingUtilities.invokeLater(new java.lang.Runnable(){

public void run(){

[Control instance].requestFocus();

}

});

Shrinking JList

noreply@blogger.com (Ravindra Gullapalli) — Mon, 12 Sep 2011 00:49:00 +0000

While using JList, the width will be adjusted automatically depending on the values present in that. JList considers value with maximum length while adjusting the width.

Depending on the situation, sometimes we may need to have fixed width for JList irrespective of the values present in that.

Use these two lines to achieve that. First line specifies the width and the second line specifies the height. Use according to the requirement.

[JList instance].setFixedCellWidth([Width]);

[JList instance].setFixedCellHeight([Height]);

One or more system components that the service pack requires are missing - Windows Vista Service Pack 2 (SP2)

noreply@blogger.com (Ravindra Gullapalli) — Mon, 12 Sep 2011 00:29:00 +0000

Fighting with my laptop since a year to install SP2 for my Windows Vista Home Premium and getting the error "One or more system components that the service pack requires are missing". Microsoft has provided a solution here which was not helpful for me.

Finally, I found a solution today here.

Solution in brief

Note: Do the registry changes mentioned in this post at your own risk. Any unknown and unwanted changes to the registry will make windows non-functional. Take registry backup before editing.

Uninstall vLite (If installed)

Go to Start Menu => regedit

Delete the key HKEY_LOCAL_MACHINE\SOFTWARE\vLite

Thats it. Hope this helps to someone who is facing the same issue.

Annoying Error "Windows has blocked some startup programs" - Windows Vista

noreply@blogger.com (Ravindra Gullapalli) — Mon, 12 Sep 2011 00:10:00 +0000

Note: Use the program mentioned in this post at your own risk. Any unknown and unwanted changes may make windows non-functional. Take registry backup before using the program.

These days I started getting this error after adding some programs in windows start-up. You will get a balloon popup specifying this error every time you start the computer. The icon which comes along with this balloon popup provides the option to start the programs manually.

This is good in terms of security so that no malicious software can damage your computer. But there are few programs which we really require and we trust for which this message is not necessary.

For those programs, this message is annoying to few of us because we do want those programs in the start-up and the solution provided by Microsoft is here

But to avoid this message completely (only for those software which you trust), a small utility Startup Unblocker is available.