ADO: ActiveX Data Objects

Managing Multiple Transactions

Transaction management is used to maintain the integrity of a data source when operations on one or more data sources need to be treated as a single operation.

The most common example of transaction management comes from banking. Take, for instance, the steps involved in transferring money from a savings account to a checking account. First, you must remove the desired amount of money from the savings account, and then that amount must be added to your checking account. Suppose that somebody walked by and pulled the plug of the ATM machine just when it had completed removing your money from your savings account, but before it added it to your checking account.

By using three methods (BeginTrans, CommitTrans, and RollbackTrans), you can create single transactions from multiple operations.

Tip

The BeginTrans, CommitTrans, and RollbackTrans methods are not available when you are using a client-side Connection object with RDS.

Starting a Transaction: The BeginTrans and CommitTrans Methods

A transaction begins with a call to a Connection object’s BeginTrans method and ends with a call to the CommitTrans method. The CommitTrans method indicates that the transaction is completed and that the data should be saved, or committed, to the data source.

The following code illustrates the use of the BeginTrans and CommitTrans methods:

' begin a new transaction con.BeginTrans ' ' do some manipulation of the data here ' ' commit the manipulations of the data to the data ...