My IT Notebook

List Tables and Columns of an MS Access Database

2007-10-31T08:40:00.001-07:00

Public Function GetTableList() As DataTable
        Try
            oConn.Open()
            Dim restrictions As String() '= {"", "", "", "Table"}
            ReDim restrictions(3)
            restrictions(3) = "Table"
            Dim dt As DataTable = oConn.GetSchema("Tables", restrictions)
            If Not IsNothing(dt) Then
                If dt.Rows.Count >= 1 Then
                    Return dt
                End If
            End If
            Throw New Exception("No tables found on database.")
        Catch ex As Exception
            Throw ex
        Finally
            oConn.Close()
        End Try
    End Function

Public Function GetColumnList(ByVal TableName As String) As DataTable
        Try
            oConn.Open()
            Dim restrictions As String()
            ReDim restrictions(3)
            restrictions(2) = TableName
            Dim dt As DataTable = oConn.GetSchema("Columns", restrictions)
            If Not IsNothing(dt) Then
                If dt.Rows.Count >= 1 Then
                    Return dt
                End If
            End If
            Throw New Exception(String.Format("No columns found on table:{0}.", TableName))
        Catch ex As Exception
            Throw ex
        Finally
            oConn.Close()
        End Try
    End Function

Enable Session Management on PHP

2007-10-29T08:22:00.000-07:00

After a basic installation of Apache and PHP, the $_SESSION global variable is not usable and it will not work if you want to transfer data on a unique user session (if you have two different browsers on a website, then it is two different sessions).

To enable the session access on PHP, do the following:

Go to your PHP installation folder (Windows) or under the /etc folder (UNIX)
Open the PHP.ini file
Search for the "Session auto-start" section and set it to "ON"
Restart or web server

Enable WS-FTP Pro Access on UNIX

2007-10-28T06:48:00.000-07:00

Using the basic PSFTP program to transfer files to a Free BSD Unix installation will take so much pain specially when copying multiple files contained in a folder. Since Free BSD Unix basic secure transfer protocol is SFTP/SSH you should use FTP utilities that can use SFTP/SSH protocol and one convenient application is WS-FTP. You can download it for trial and buy it afterwards.

However, by default Free-BSD Unix don't accept WS-FTP connections. You have to configure it so that you will have the convenience of transferring files by drag and drop. Follow this simple steps:

Go to path /etc/ssh/sshd/
Edit file sshd_config using VI or other file authoring tools
Search for PasswordAuthentication and change YES to NO
Restart your Unix installation

Drop Down Ruby on Rails Control

2007-10-27T09:35:00.000-07:00

Here's the syntax:

form.collection_select :reportType_ID, @report_types, :id, :name

Where:

:reportType_ID (form attribute/param)
@report_types (data collection obj)
:id (represents the display value)
:name (represents the display text)

Rush Project Estimation

2007-10-22T20:40:00.000-07:00

I discovered a useful online tool that a project development team can use to estimate the time line for a certain project: Planning Poker.

This tool is free and it utilizes Web 2.0 for the collaboration of team members on the website to try estimating the total man days using cards. At first a project functionality is brought up by the moderator then all participating members will choose from the cards for their own estimation. After all has picked their cards, all of them will show their cards and discuss their estimates.

This promotes agile/rush project planning that allows the participation of credible team members. The service also assures privacy on all users and will not disclose any discussion/deals that took place on the team session.

Executing Executables through ASP.NET

2007-06-07T18:58:00.001-07:00

Given:

Web Technology: ASP.NET 1.1, Magic Ajax
Database: MS SQL 2000

Requirements:

Execute a console application created through VB.NET 2003, this application accepts 1 parameter that determines what type of file to generate and generates a text file based on the application settings
Display status of execution

Code Snippet:

Private Function execute(ByVal FileType As String) As Boolean
Dim startInfo As ProcessStartInfo
Dim pStart As New Process
Dim path As String
Dim strErr As New System.Text.StringBuilder
path = "c:\GPS_Data_Scrubber.exe"
startInfo = New ProcessStartInfo(path)
startInfo.Arguments = FileType
pStart.StartInfo = startInfo
Try
pStart.Start()
pStart.WaitForExit()
If pStart.ExitCode = 0 Then
Return True
Else
With strErr
.Append("An error occurred while processing: " & FileType & ".")
.Append("
Please check the error log for details.")
End With
Me.lblError.Text = strErr.ToString
Me.lblError.Visible = True
Return False
End If
Catch ex As Exception
lblError.Visible = True
Me.lblError.Text = ex.Message
End Try
End Function

Problem and Solutions

Problem #1

When I try to execute the console application, an error occurs: the system cannot find the file specified

Analysis

I assumed that using System.Environment.CurrentDirectory as my rootFolder on the Console Application is not advisable since I am not sure what current directory my console application will use that is why i specified drive C: as my root folder

Solution

The reason the system can not find the file specified is because of security reasons, ASP.NET process has no rights to execute the console application.

Problem #2

When I specified drive C, my ASP.NET web app was able to execute the console application to some extent: it was able to execute a stored procedure for my data extraction. However, it was not able to generate the text files that the console application can normally do when I execute it manually.

Analysis:

Since I specified drive C as the console applications working folder, the ASP.NET worker process maybe has no rights to write file to it.
I thought maybe changing the virtual folders permissions to Execute might solve the problem, however, my web app was able to execute it still even though I did not specified it in the first place

Solution:

Create a new folder with security permission of Everyone Full Control on it and specify in the console application as its working folder using the Application Configuration File

An Intro

2007-06-07T18:54:00.000-07:00

Well is it quite obvious in the title, this blog is all about my daily discoveries, notes, and insights in my IT Development World. I will post all of my problems and its corresponding solutions and all of you guys out there reading this are free to post your comments anytime.