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called a “paired constraint”) specifies multiple properties whose combined
values are unique. For example, you can constrain the combined
Street_Number, Street_Name, and City fields to uniquely identify a
building address.
■ Click New (under Specify Constraints (And The Order)).
■ Select the boxes for the properties that must have unique values.
The properties designated as unique appear in the list at the bottom
of the dialog box.
■ If desired, use the up and down arrows for the list to change the order
of the properties.
5 Click Apply.
Exposing a Native Database View in a Schema
A database view is a virtual or logical table composed of the result set of a
query. Unlike ordinary tables in a relational database, a view is not part of the
physical schema. It is a dynamic, virtual table computed from data in the
database. Changing the data in a table alters the data shown in the view.
Views can provide advantages over tables:
■ You can use a view to make a subset of data available to certain users.
■ A view can join and simplify multiple tables into a single virtual table.
■ Views can aggregate data (using a sum, average, or other function) to
calculate and present data.
NOTE This functionality affects geospatial feature data only. For information about
linking records in an external database to objects in a drawing, see
Overview of
Linking Database Records to Objects
(page 522). For information about moving
data between DWG and geospatial data stores, see
Migrating DWG Data to GIS
(page 628).
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