Question

Please help me… i am trying to update my database from VB.net. It shows error. My code is given below….

Try
            getConnect()

            Dim strSQL As String
            strSQL = " UPDATE DEPARTMENT SET [DEP_ID]=@DEP_ID,[DEPART]=@DEPART,    [DEP_DSCRPTN]=@DEP_DSCRPTN WHERE [DEP_ID] = @DEP_ID"
            Dim cmd As New SqlCommand(strSQL, Conn)
            cmd.Parameters.AddWithValue("@DEP_ID", CInt(Me.DEPID.Text))
            cmd.Parameters.AddWithValue("@DEPART", SqlDbType.VarChar).Value =     CMBDEPT.Text
            cmd.Parameters.AddWithValue("@DEP_DSCRPTN", SqlDbType.VarChar).Value =     TXTDESC.Text
            Conn.Open()
            cmd.ExecuteNonQuery()
            MsgBox("Update Complete!", MsgBoxStyle.Information, "Update")
        Catch ex As Exception
            MsgBox("ERROR: " + ex.Message, MsgBoxStyle.Information, "Update")
        Finally
            Conn.Close()
            BTNCLEAR.PerformClick()
        End Try

And the error is:

ERROR: Cannot update identity column ‘DEP_ID’

Answer 1

The error message is clear, remove the Set DEP_ID = @DEP_ID part.

Try
    getConnect()

    Dim strSQL As String
    strSQL = "UPDATE DEPARTMENT SET [DEPART]=@DEPART," + 
             "[DEP_DSCRPTN]=@DEP_DSCRPTN WHERE [DEP_ID] = @DEP_ID"
    Dim cmd As New SqlCommand(strSQL, Conn)
    cmd.Parameters.AddWithValue("@DEP_ID", CInt(Me.DEPID.Text))
    cmd.Parameters.AddWithValue("@DEPART", SqlDbType.VarChar).Value =     CMBDEPT.Text
    cmd.Parameters.AddWithValue("@DEP_DSCRPTN", SqlDbType.VarChar).Value =     TXTDESC.Text
    Conn.Open()
    cmd.ExecuteNonQuery()
    MsgBox("Update Complete!", MsgBoxStyle.Information, "Update")
Catch ex As Exception
    MsgBox("ERROR: " + ex.Message, MsgBoxStyle.Information, "Update")
Finally
    Conn.Close()
    BTNCLEAR.PerformClick()
End Try

If you find yourself in need to change an Identity column then I think you need to analyze better your database schema.