Microsoft® SQL Server 2012 Unleashed

Implicit Transactions Versus Explicit Transactions

When would you want to use implicit transactions versus explicit transactions? If you are porting an application from another database environment, such as DB2 or Oracle, that uses implicit transactions, that application converts over to SQL Server more easily and with fewer code changes if you run in implicit transaction mode. Also, if the application you are developing needs to be ANSI-compliant and run across multiple database platforms with minimal code changes, you might want to use implicit transactions.

If you use implicit transactions in your applications, you need to be sure to issue COMMIT statements as frequently as possible to prevent leaving transactions open and holding locks for ...