• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 176
  • Last Modified:

How do I make a series of ADO sql statements atomic??

I have a series of 5 sql executes with my ADO object and I need them to either all execute or on error I need to rollback everyone that has previously executed.
0
mccainz2
Asked:
mccainz2
1 Solution
 
dbirdmanCommented:
Use the ADO Connection object for Transaction Processing.
Prior to executing your sql statements, begin the transaction with:  cn.BeginTrans.  If one of the sql executes gets an error, use cn.RollbackTrans.  If they all complete successfully, use cn.CommitTrans.  I'm using this now in an app and it works great.

Good Luck
0
 
dbirdmanCommented:
This may be a better examplen for the transaction.  The connection string is for SQL Server; just substitute it for the appropriate connection if you're not using SQL Server.  The Rollback will also handle any updates you may have done to a table within the Transaction.

Public Function Test() As Boolean

Dim cn As ADODB.Connection
Dim rs1 As ADODB.Recordset
Dim rs2 As ADODB.Recordset
Dim strConnection As String
Dim sql1 As String
Dim sql2 As String

Set cn = New ADODB.Connection
Set rs1 = New ADODB.Recordset
Set rs2 = New ADODB.Recordset

cn.ConnectionString  = "Provider=SQLOLEDB;DataSource=MyServer;Initial Catalog=My Database; User ID=MyID; Password=MyPW"

cn.Open

sql1 = "Select * from Table1"
sql2 = "Select * from Table2"

'Begin Transaction
cn.BeginTrans

rs1.Open sql1, cn, adOpenDynamic, adLockPessimistic, adCmdText
  'Stop, for example, if no records are retrieved
If rs1.EOF Then
     cn.RollBackTrans
     Exit Function
End If

rs2.Open sql2, cn, adOpenDynamic, adLockPessimistic, adCmdText
  'Stop again if no records are retrieved
If rs2.EOF Then
     cn.RollBackTrans
     Exit Function
End If

'If no problems, commit the transaction
cn.CommitTrans

Test = True

End Function

Hope this helps

0
 
Valliappan ANSenior Tech ConsultantCommented:
You can have a error handler, and in the error handler, you can place the rollback code, so that, if any error happens when executing one of the sql statements or whatever, then a rollback would occur.

The code could be something like this:

Dim lTrans As Boolean

On Error Go To ErrHandler
lTrans = False
:
:
Conn.Begintrans
lTrans = True
:
:
your sql statements here
:
:
Conn.CommitTrans
lTrans = False
:

ErrHandler:
If Err.Number <> 0 Then
   Msgbox "Could Not Proceed." & Err.Description & " :" & Err.Number
   If lTrans Then
     Conn.RollbackTrans
     lTrans = False
   End If
End If
0
 
mukunthCommented:
As suggested in other comments u can use the transaction as follow:

cn.Begintrans
.
.
.
(execute the 5 SQL statements here by saying cn.Execute )
cn.execute "insert into test values(1)"
.
.
If cn.Errors.Count > 0 Then
cn.RollBackTrans
Msgbox "errors occured"
else
cn.CommitTrans
End If

where:
cn is the connection object
Hope this helps.
Cheers.
0
 
mccainz2Author Commented:
danka, for some idiotic reason I was assuming that on error it would behave by rolling back without me actually writing any error handling code....silly goose.
0

Featured Post

Receive 1:1 tech help

Solve your biggest tech problems alongside global tech experts with 1:1 help.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now