Message mapping

Message mapping provides you with a great deal of flexibility when assigning values from input sources to output targets. In the most basic form of mapping, field-to-field assignments are made directly between messages. Through the Compose Expression editor, extra value can be added to further define the mapping conditions as appropriate.

Mapping provides a very simple way to transform data from a source to a target value, but the exact mapping options available are not the same for all node types.

Target assignments can be calculated or combined from various input sources, which can be in the form of messages or database tables as with many-to-one or many-to-many mapping. Target assignments can also be conditional, based upon a combination of deciding factors, which can be applied to any type of mapping.

Before trying to add a message as an input or output, define and import into the workspace a message set with the appropriate messages. Correspondingly, database tables must be imported into the workspace.

Note: Commit changes to the message definitions and database tables before importing messages or tables. If a message or database table is added to a mapping routine, and changes are subsequently made to it, those changes are not immediately visible in the mapping file. One of the following two conditions applies:
  • If the mapping file is open when a definition change is made and committed, a dialog asks if you would like the mapping view refreshed to reflect the changes, or if you would like to ignore them for now. Even if minor definition changes are made that do not trigger this prompt, the explicit closing and reopening of the mapping file brings all definitions up to date.
  • If the mapping file is closed when a change is made, the next opening of the mapping file shows the changes made, and all previous mappings are preserved. Any mapping that contains broken references as a result of changes definition changes is highlighted.

A Mapping node automatically generates an ESQL module that creates an output message (if necessary), and then calls the mapping procedure. The mapping procedure has, as its parameters, references to the element complex types of the global message element. The complex type itself does not have to be global or named. It can be a local anonymous type.

Mapping supports reuse through ESQL functions, and mappings can also call user-defined ESQL routines. Mappings are not reusable with other mappings.

Related concepts
Mappings
Message flows
Message modeling
Related tasks
Developing mappings
Related reference
Mapping node
Mappings