Object -
streams
:
Select
The Select
object represents the select clause. Anything that comes under select clause like aggregator function
invocations are also handled in this processor. Further, grouping of the events (provided by the groupby clause) is
also performed in this processor. aggregatorArr
is an array of aggregators which are used in the select clause.
groupbyFuncArray
is an array of function pointers which returns the values being grouped. selectFunc
is a
function pointer to a lambda function which creates the data
field of the output stream event. scopeName
is
used as a breadcrumb to identify the select clause if there are multiple forever
blocks.
Methods
Selects only the selected fields in the select clause.
Parameters
- streamEvents StreamEvent?[]
-
The array of stream events passed to the select clause.
getGroupByKey
( function(StreamEvent) returns (anydata)
[]? groupbyFunctionArray, StreamEvent e)
Creates a unique key for each group with the given values in the group by clause.
Parameters
-
groupbyFunctionArray
function(StreamEvent) returns (anydata)
[]? -
Function pointer array to the lambda function which returns each group by field.
- e StreamEvent
-
Stream Event object being grouped.
-
Return Type
(string) Returns a unique groupby key by which the event
e
is grouped.