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The Relationship Between Type and Table Hierarchies

Every table in a table hierarchy must be assigned to a named row type in a corresponding type hierarchy. Figure 32 shows an example of the relationships that can exist between a type hierarchy and table hierarchy.

Figure 32. Example of the Relationship Between Type Hierarchy and Table Hierarchy
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However, you can also define a type hierarchy in which the named row types do not necessarily have a one-to-one correspondence with the tables in a table hierarchy. Figure 33 shows how you might create a type hierarchy for which only some of the named row types have been assigned to tables.

Figure 33. Example of an Inheritance Hierarchy in Which Only Some Types Have Been Assigned to Tables
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