 Always contains the latest event, which is the event that was most recently added to a window.
Always contains the latest event, which is the event that was most recently added to a window. Satisfies the event pattern.
Satisfies the event pattern. Is always the most recent set that matches the event pattern. This is important when there is more than one set that is a candidate for the match set.
Is always the most recent set that matches the event pattern. This is important when there is more than one set that is a candidate for the match set.| pattern | The event pattern that you want to find. See Defining event patterns. | 
| block | The procedural code to execute when a match is found. See Acting on pattern matches. |