Contents for EPL Reference

Introduction and Roadmap

Document Scope and Audience

WebLogic Event Server Documentation Set

Guide to This Document

Samples for the WebLogic Event Server Application Developer

Overview of the Event Processing Language (EPL)

Overview of the EPL Language

Event Representation

Event Objects

Plain Old Java Object Events

Map Events

Event Properties

Event Sinks

Processing Model

Event Streams

Sliding Windows

Row-Based Sliding Windows

Time-Based Sliding Windows

Batched Windows

Time-Based Batched Windows

Row-Based Batched Windows

Subqueries and WHERE Clauses

Aggregation

Use Cases

Computing Rates per Feed

Computing Highest Priced Stocks

Segmenting Location Data

Detecting Rapid Fall-off

Finding Network Anomalies

Detecting Absence of Event

Summarizing Terminal Activity Data

Reading Sensor Data

Combining Transaction Events

Monitoring Real-time Performance

Finding Dropped Transaction Events

EPL Reference: Clauses

Overview of the Clauses You Can Use in an EPL Statement

SELECT

Choosing Specific Event Properties

Using Expressions

Aliasing Event Properties

Choosing All Event Properties

Selecting New and Old Events With ISTREAM and RSTREAM Keywords

FROM

Inner Joins

Outer Joins

Subquery Expressions

Parameterized SQL Queries

RETAIN

Keeping All Events

Specifying Window Size

Specifying Batched Versus Sliding Windows

Specifying Time Interval

BASED ON Clause

Specifying Property Name

Using PARTION BY Clause to Partition Window

Using WITH Clause to Keep Largest/Smallest/Unique Values

MATCHING

FOLLOWED BY Operator

AND Operator

OR Operator

NOT Operator

EVERY Operator

WITHIN Operator

Event Structure for Matched Pattern

WHERE

GROUP BY

HAVING

Interaction With MATCHING, WHERE and GROUP BY Clauses

ORDER BY

OUTPUT

Interaction With GROUP BY and HAVING Clauses

INSERT INTO

EPL Reference: Operators

Overview of EPL Operators

Arithmetic Operators

Logical and Comparison Operators

Concatenation Operators

Binary Operators

Array Definition Operator

List and Range Operators

IN Operator

BETWEEN Operator

String Operators

LIKE Operator

REGEXP Operator

Temporal Operators

FOLLOWED BY Operator

WITHIN Operator

EVERY Operator

EPL Reference: Functions

Single-row Functions

The MIN and MAX Functions

The COALESCE Function

The CASE Control Flow Function

The PREV Function

Previous Event Per Group

Restrictions

The PRIOR Function

Comparison to the PREV Function

Aggregate functions

User-Defined functions

Programmatic Interface to EPL

Java Programming Interfaces