How to use a variable value in a SELECT statement - Visual Basic Discussion Boards

How To compare data in array A and array B Smile | :)

Do U need this?

Using simple for loop
we can achieve this.

flag=true
for i=0 to n

if a(i) not equal to b(i) then
flag=false

next

if flag = false then
the arrays are not equal.

If U want something else other than this,
U will have to elaborate so that everyone can understand
what U really need.

Regards,
Arun Kumar.A

Thank You

How to use crystal report Engine 10 in vb.net and open my *.rpt
so i don't like using crviewer in .net for opening my report
help me

ahmadi

hi,
so where do you want you to view your report if you don't like to use crviewer?

Don't block the drive way of all the newbies in programming. Smile | :)

I want the user to be able to choose the colours of the title, score, lives etc

I thought if I have a text file in the folder with the colours,

Red
Yellow
Blue

How do I then transfer it to the project?
Title.color = text line one
Score.color = text line two
Lives.color = text line three

If you accept words, you may be able to use reflection if they are colors in the enum the framework provides. Otherwise, you need a lookup table to establish what "Red" means, if it's Colors.Red, or if it's 0XFF0000, or whatevr.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

Hello all,

Does anyone know how to use variable values in SELECT statements?

Thanks

The obvious way is to concatenate strings. The better way is to write a stored procedure. Either way, you need to be careful of SQL injection attacks.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

hello

i have generated one datagrid using dataset having columns user_id,initial,passwd,access etc. From these i am displaying only 3 columns my query is -
select user_id as user,user_init as inital,user_nm as name
from user_mast

but i am facing one problem i.e. after adding new record in dataset my datagrid is displaying all columns including passwd also which is not to be shown.

Pliz. guide me how i solve this problem?

thanks

reply immediate
thanks

Hi,
You should set AutoGenerateColumn to False

hi,
try to insert a query again using select statement after you add your record. to show specific column you want to show.

Don't block the drive way of all the newbies in programming. Smile | :)

Visual Basic 2005
I used DataSet Designer to add a column called "Case#" to an existing SQL table.
The table is used by a DataGridView in a VB 2005 program.
I got it working on my development computer in debug mode.
Then, when I installed it, I got an exception "Case# is an invalid column" and none of my data records appeared.

Adding the following statement did not help:
PatientDataSet.Patient.Columns.Add("Case#")

You asked this three times....

If you have a grid, you can add columns to it, this will not change your database, but just the data you have in memory.

I'm not sure if you can run SQL to add a column within your code. I'd certainly be asking why you'd do such a thing, instead of fixing your SQL and making your schema established and solid.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

I have a commercial application with a number of customers running it. I need to add a column to one of the SQL tables. So, I have to do it within my code.

OK, try writing the SQL to alter the table and running it from code.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

I have a number of users running this application in remote locations.
Of course, they cannot lose their existing data.
It was requested that I include a column called "CaseNbr" in the table.
The file that I need to add the column to is an SQL table that is being updated via a DataGridView.
I think that it was a mistake to add the column via DataSet Designer, so, I restored my project from a backup eliminating that step.
So, now the column does not exist in the database and I am back to square one.
I would like to add the column to the SQL tables via my app so that my various users can have it added to their databases. Every user has his own database.
There is only one program that accesses the table and it is very simple.
The user selects (or adds) a row (Patient record) then the program simply passes that Patient's info to the main form of the application.
I know nothing about SQL. There are no SQL statements in my app. Everything is done by TableAdapter and BindingSource statements like:
Me.PatientTableAdapter.Fill(Me.PatientDataSet.Patient)
PatientBindingSource.Position = Form1.DefaultPatient
That's why I don't know how to add a column to the SQL table.

I added the following statement to my program:

Me.PatientDataSet.Patient.Columns.Add("CaseNbr", Type.GetType("System.String"))

But it did not do anything.

I added the statement as the first command in the Form Load routine:

Public Class Patient
Public Sub Patient_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Me.PatientDataSet.Patient.Columns.Add("CaseNbr", Type.GetType("System.String"))
Me.PatientTableAdapter.Fill(Me.PatientDataSet.Patient)
PatientBindingSource.Position = Form1.DefaultPatient
End Sub

I have a number of users running this application in remote locations.
Of course, they cannot lose their existing data.
It was requested that I include a column called "CaseNbr" in the table.
The file that I need to add the column to is an SQL table that is being updated via a DataGridView.
I think that it was a mistake to add the column via DataSet Designer, so, I restored my project from a backup eliminating that step.
So, now the column does not exist in the database and I am back to square one.
I would like to add the column to the SQL tables via my app so that my various users can have it added to their databases. Every user has his own database.
There is only one program that accesses the table and it is very simple.
The user selects (or adds) a row (Patient record) then the program simply passes that Patient's info to the main form of the application.
I know nothing about SQL. There are no SQL statements in my app. Everything is done by TableAdapter and BindingSource statements like:
Me.PatientTableAdapter.Fill(Me.PatientDataSet.Patient)
PatientBindingSource.Position = Form1.DefaultPatient
That's why I don't know how to add a column to the SQL table.

You cannot add a column to the database by addings it to the dataset. You have to write the SQL statement to modify the SQL stored database and execute it from your code. THEN you can modify your application to support the new database schema.

furjaw wrote:
I know nothing about SQL.

And you have customers who depend on you knowing this...? I suggest you learn, real quick. If you don't, you won't have any more customers.

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007

Ok, I don't actually have any customers, yet.
But, I have one beta tester using it live and he cannot lose the data that he has entered so far.
I am thinking ahead - if I had to add a column to a table after I have a number of users with their own databases, I have to be able to add a column programmatically. I have exactly that situation right now even though I only have one user.

It is probably a total of 3 statements that I would have to add to my Visual Basic 2005 program. One of them is:

ALTER TABLE Patient ADD CaseNbr Varchar(10)

But, I don't know what the other 2 are.

OK, here is my programming attempt:

Imports System.Data.SqlClient
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim sqlConnection As New System.Data.SqlClient.SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\patient.mdf;Integrated Security=True;User Instance=True")
Dim command As New System.Data.SqlClient.SqlCommand
command.CommandText = "ALTER TABLE Patient ADD CaseNbr Varchar(50)')"
sqlConnection.Open()
command.ExecuteNonQuery()
sqlConnection.Close()
End Sub
End Class

I got the following error when I executed:

An attempt to attach an auto-named database for file C:\Documents and Settings\Owner\My Documents\Visual Studio 2005\Projects\Add Column\Add Column\bin\Debug\patient.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.

Here is another attempt:

Imports System.Data.OleDb
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim Sql As String = "ALTER TABLE Patient ADD CaseNbr Varchar(50)"
Using connection As New OleDbConnection("Data Source=.\SQLEXPRESS;Provider=SQLOLEDB;AttachDbFilename=|DataDirectory|\Patient.mdf;Integrated Security=True;User Instance=True")
Using command As New OleDbCommand(Sql, connection)
connection.Open()
command.ExecuteNonQuery()
connection.Close()
End Using
End Using
End Sub
End Class

It aborted with the following message:

No error message available, result code: DB_E_ERRORSOCCURRED(0x80040E21).

The connection string is wrong. You haven't told it what the database name is. Without that, it'll try to attach the same database file again, resulting in the error you got.

Driver={SQL Native Client};Server=.\SQLExpress;AttachDbFilename=|DataDirectory|mydbfile.mdf;Database=dbname;Trusted_Connection=Yes;

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007