[RESOLVED] Get result of a query (single value) into a Visual Basic label

[joecruz36]

I'm performing a SELECT query to get the student ID. I'm getting the following error:

Conversion from String "SELECT est_ID FROM ESTUDIANTE WH" tp type 'Long' is not valid

Here is the code:

Try
Using Con As New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=" & globalvariable.dbpath
& ";Integrated Security=True;User Instance=True")
Con.Open()
Using com As New SqlCommand("SELECT est_id FROM ESTUDIANTE WHERE est_nombre ="
& Val(txtNombre.Text) And "est_apellido =" & Val(txtApellido.Text), Con)
Dim textObj = com.ExecuteScalar
If Not textObj Is Nothing AndAlso Not textObj Is DBNull.Value Then
txtID.Text = CInt(textObj)
End If
End Using
End Using

Catch ex As Exception
MessageBox.Show(ex.Message)

End Try

THX...

[si_the_geek]

Welcome to VBForums

Read that line a bit more carefully... here is the SQL statement part with colouring to make it a bit clearer what is a string and what isn't:

"SELECT est_id FROM ESTUDIANTE WHERE est_nombre =" & 
Val(txtNombre.Text) And "est_apellido =" & Val(txtApellido.Text)

The word And does not belong where it is (it should be inside the string, and that string should be appended to the rest as you do with the other parts).

[joecruz36]

Thanks for the tip. It worked.
Here is the code corrected:
Try
Using Con As New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=" &
globalvariable.dbpath & ";Integrated Security=True;User Instance=True")
Con.Open()
Using com As New SqlCommand("SELECT est_id FROM ESTUDIANTE WHERE est_nombre LIKE '" &
txtNombre.Text & "%'AND est_apellido LIKE '" & txtApellido.Text & "%'", Con)

Dim textObj = com.ExecuteScalar
If Not textObj Is Nothing AndAlso Not textObj Is DBNull.Value Then
txtID.Text = CInt(textObj)
End If
End Using
End Using

Catch ex As Exception
MessageBox.Show(ex.Message)

End Try

[si_the_geek]

No problem


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