When you use the built-in nodes Compute, Database, and Filter, you must customize them to determine the exact processing that they provide. To do this, you must create, for each node, an ESQL module in which you code the ESQL statements and functions to tailor the behavior of the node, referring to message content, or database content, or both, to achieve the results that you require. ESQL modules are maintained in ESQL files, managed through the Broker Application Development perspective.
This section provides information on: