Extensions (.xem files) provide means for
customizing and extending PowerDesigner metaclasses, parameters, and generation. Extended
models can be used to store additional information, or to change model behavior.
PowerDesigner provides four
.xem
files:
- ESPSchema.xem – extensions for an logical data model. Contains rules and
code that let you model ESP Schema in a
PowerDesigner logical data model.
- IQ.xem – extensions for a physical data model. Contains only
transformation rules needed to convert an
ESP Schema definition to an
SAP Sybase IQ table definition, in an
SAP Sybase IQ model.
- ASE.xem – extensions for a physical data model. Contains only
transformation rules needed to convert an
ESP Schema definition to an ASE table
definition, in an ASE model.
- HANA.xem – extensions for a physical data model. Contains only transformation rules
needed to convert an ESP Schema definition
to an SAP HANA table definition, in a HANA model.
When you use the models provided with PowerDesigner, the extensions are present.
When you create a new model using the ESP model category
set, extensions are applied automatically.
When you create a new model without using the ESP
Model categories, or when you have an existing model you can extend it using the
PowerDesigner tools and ESP extension files.