Stream Clause

Use of Accept:New and Accept:All

Events and concepts (entities) can be deleted by rules. By default (accept: all), if a continuous query has already seen an entity before, then it will expect a delete or modify notification from the cache cluster. Therefore the query must keep track of such things.

However, if you specify the accept: new clause, then the continuous query does not have to track such things, and the memory footprint of the query is reduced.

The accept:new clause is required for event stream processing (ESP) queries. See Event Stream Processing (ESP) Queries.

Use of Emit: New and Emit: Dead

The emit keyword determines whether the query is evaluated when an entity enters the window (emit : new) or when an entity leaves the window (emit : dead).

The default value is emit : new.

For examples showing usage, see the following:

• Using Emit New to Create a Counter
• Delaying Output with an Emit Dead Clause