Data Transformation Engine Introduction to the Design Studio

Chapter 3 - Type Designer Type Trees
Introduction to the Design Studio
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Type Trees
A type tree is a data dictionary because it contains a collection of type definitions.
Each type tree is created and managed in the Type Designer. Type trees have a
file name extension of .mtt. Each icon in a type tree identifies a data type.
The tree has a root type and other types are connected to the tree through
branches of the tree. The root type is the base type from which all other types
stem, representing the data objects of all the types in the tree. The type tree
window does not show the layout or composition of the data. The group window
defines the layout and composition of the data.
In the type tree, the data content is not identified as the source or the target data.
The input and output designations of the data are specified in the Map Designer.
The Type Designer defines the specific properties of the data.
Classification Hierarchy
The types in a type tree are arranged in a classification hierarchy. If a type is
subordinate to another type, it is called a subtype. The type on the branch
stemming above a specific type is called its supertype. The deeper the subtype is
in the type tree, the data characteristics become more specific. Subtypes are
specific entities of the supertype. The following example illustrates this hierarchy:
♦ Subtype1, Subtype2, and Subtype3 are
subtypes of Type
♦ Type is a subtype of Supertype
♦ Supertype is a subtype of Root.