Defining Simple Data Types 
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1. Create a data type in your namespace on the design maintenance screen of the Integration Builder (see: Creating a New Object).
2. Choose the Definition tab page. The XSD editor automatically selects the category Simple Type when you create a data type.
3. In the Type column, define a built-in data type by double clicking the cell and copying a value from the list box.

You can also reference other simple data types in the toolbar or in the list box by using the search help. You cannot reference complex data types.

You cannot make any entries for simple data types in the Occurrence column.
4. To define the facets of the simple data type in the Details column, call the input help by double clicking.
5. Enter a description for your simple data type.
6. Save your changes.
You can now use your simple data type in other data types or (fault) message types.