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SAS Component Language: Reference

Preserving the Integrity of Data

SCL provides a group of functions that specify and enforce integrity constraints for SAS tables. Integrity constraints preserve the consistency and correctness of stored data, and they are automatically enforced for each addition, update, and deletion activity for a SAS table to which the constraints have been assigned. For such a table, value changes must satisfy the conditions that have been specified with constraints.

There are two basic types of integrity constraints: general constraints and referential constraints. The following list shows the specific types of integrity restraints that you can apply through SCL. The first four items are general constraints, which control values in a single SAS table. The last item is a referential constraint, which establishes a parent-child relationship between columns in two or more SAS tables.

SCL provides the following functions for creating and enforcing integrity constraints:

creates and specifies integrity constraints for a SAS table.

drops an integrity constraint.

returns the type of constraint that is assigned to a SAS table.

returns the varlist or WHERE clause that is associated with an integrity constraint.

For more information about integrity constrains, see SAS/SHARE User's Guide.

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