Event data-field filter that supports simple or complex queries.
Filter results are evaluated using a compound predicate that can include standard query operators to determine if the event handler matches the event.
FilterSpec queries use standard comparison operators, including:
FilterSpec="[attr1] IS NOT NULL OR [attr2] LIKE 'value*'"
where attr1 and attr2 are event data fields and value represents part of a comparison value for attr2. In this example, the event handler is evaluated for a match if attr1 is not empty or if attr2 is like the value of "value*".
Here is another example:
In this example, @UserName is macro-expanded before the query is performed.
The Filter and FilterSpec parameters can be used together to evaluate event data-field data received with the device event associated with this event handler. Evaluations using the Filter parameter (AND conditions) occur before evaluations using the FilterSpec parameter (compound predicate).
See also the descriptions for the Filter event handler parameter and the QuerySpec event response parameter.