Accomplish most common querying tasks using a set of queries available in the Visual editor: filter, aggregate, join, compute, union, and pattern.
The tools for these six queries are available as objects in the Palette, in Streams and Windows.
Filter – allows you to filter a stream down to only the events of interest, based on a filter expression.
Aggregate – allows you to group events that have common values and compute summary statistics for the group, such as an average. You can also define a window size, based on either time or number of events.
Join – allows you to combine records from multiple streams or windows, forming a new record with information from each source.
Compute – allows you to create a new event, with a different schema from the input, and compute the value to be contained in each column (field) of the new event.
Union – allows you to combine multiple streams or windows that all share a common schema into a single stream or window.
Pattern – lets you watch for patterns of events within a single stream or window or across multiple streams and windows. When ESP Server detects an event pattern in a running project, it produces an output event.