I want my workflow to execute only once for a record. For example: I am having an opportunity when it reaches the Amount of $10000, it should trigger an email from workflow. It is happening now. But when it comes below to $10000 and reaching $10000 again it is sending the email again, which should not happen in my scenario.
Note: I tried using sales force default big deal alert functionality. But, in my case it cannot be used.
Please help in this.