Reading and Editing Registry Keys

First, you need to import Microsoft.win32.

Sample code for edit the registry

Public Shared Sub UpdateiPhysicalFlagTo0()
Dim regConnectionKey As RegistryKey
regConnectionKey = Registry.LocalMachine.OpenSubKey("key here", True)
If (regConnectionKey Is Nothing) Then
regConnectionKey.Close()
Else
Try
regConnectionKey.SetValue("FirstTimeTrain", "0")
regConnectionKey.Close()
Catch er As Exception
Throw New Exception(er.Message)
End Try
End If
End Sub

Sample code for reading registry

Public Shared Function GetRegistryFirstTimeTraining() As Boolean
Dim bool As Boolean = False
Dim regConnectionKey As RegistryKey
regConnectionKey = Registry.LocalMachine.OpenSubKey("SOFTWARE\\SQLView\\DMSConnection")
If (regConnectionKey Is Nothing) Then
Throw New Exception("GetRegistryFirstTimeTraining() : The registry key is not found")
Else
Try
Dim vr As String
vr = regConnectionKey.GetValue("FirstTimeTrain")
regConnectionKey.Close()
If (vr.ToString() = "1") Then
bool = True
End If
Return bool
Catch er As Exception
Throw New Exception(er.Message)
End Try
End If
End Function

IDIOTIC Me Missing Dlls

When an application I was developing failed to work in the deployment area, I struggled hard to find the bug, and the clause of the problem.

Like most novice programmers, I concentrated on the code, twinking here and there, trying to get it working. But tried as I might, I could not find the clause of the problem. Finally I could not bear it any longer, approached my supervisor for help to trace the problem.

My supervisor, Sindy, is a smart lady, who immediately look at the dll.. And discovered that one dll is missing from the deployment package. When she inserted the missing dll, the whole thing work well.

Lesson Learnt and Humble pie eaten: Always check the dll when you are deploying to a the deployment area to make sure no missing dll. This save you a lot of time in the long run. Missing dlls are very hard to trace and problematic.

Oracle and Autonumber

Oracle does not have an autonumber like SQLServer has. Oracle's way to for autonumbers is using sequences and triggers. The sequence makes sure that unique numbers are generated while the trigger fills the these numbers into the column for which an autonumber is desired. This is demonstrated in the following. I need a table with a autonumber column. In this case, it will be column id. create table tbl_autonumber( id number primary key, txt varchar2(20) ); Then, the sequence: create sequence seq_autonumber; And the trigger. It fires whenever a new record is inserted and assigns the sequence's next value (using nextval) to :new.id. create trigger trg_autonumber before insert on tbl_autonumber for each row begin select seq_autonumber.nextval into :new.id from dual; end; / Now, three records are inserted: insert into tbl_autonumber (txt) values('bar'); insert into tbl_autonumber (txt) values('baz'); insert into tbl_autonumber (txt) values('qqq'); select * from tbl_autonumber; The trigger did its job and filled id with unique values: ID TXT 1 bar 2 baz 3 qqq Now, trying to circumvent the 'autonumber' and specify an aribtrary id: insert into tbl_autonumber (id, txt) values(100, '###'); insert into tbl_autonumber (id, txt) values(200, '???'); insert into tbl_autonumber (id, txt) values(300, '!!!'); Doesn't work, is overwritten by trigger! select * from tbl_autonumber; ID TXT ---------- ------------------------- 1 bar 2 baz 3 qqq 4 ### 5 ??? 6 !!! Changing the trigger and ... create or replace trigger trg_autonumber before insert on tbl_autonumber for each row begin if :new.id is null then select seq_autonumber.nextval into :new.id from dual; end if; end; / .... trying again to overrule the trigger: insert into tbl_autonumber (id, txt) values(111, 'This'); insert into tbl_autonumber (id, txt) values(222, 'should'); insert into tbl_autonumber (id, txt) values(333, 'work'); And indeed, it worked. However.... select * from tbl_autonumber; ID TXT ---------- -------------------------------------- 1 bar 2 baz 3 qqq 4 ### 5 ??? 6 !!! 111 This 222 should 333 work .... it should be clear that it is a bad idea to supply primary keys if there is a sequence.