Table of Contents

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  1. Preface
  2. Introduction to Test Data Management
  3. Test Data Manager
  4. Projects
  5. Policies
  6. Data Discovery
  7. Creating a Data Subset
  8. Performing a Data Masking Operation
  9. Data Masking Techniques and Parameters
  10. Data Generation
  11. Data Generation Techniques and Parameters
  12. Working with Test Data Warehouse
  13. Analyzing Test Data with Data Coverage
  14. Plans and Workflows
  15. Monitor
  16. Reports
  17. ilmcmd
  18. tdwcmd
  19. tdwquery
  20. Appendix A: Data Type Reference
  21. Appendix B: Data Type Reference for Test Data Warehouse
  22. Appendix C: Data Type Reference for Hadoop
  23. Appendix D: Glossary

Computed Columns

Computed Columns

Computed columns are columns that contain data determined by data in other columns.
For example, an
Employee_Salary
table contains columns
Emp_ID
,
Basic_Salary
,
Allowances
,
Tax_Deduction
, and
Net_Pay
.
Net_Pay
is a computed column that is calculated as
Basic_Salary + Allowances - Tax_Deduction
. The database populates the data in
Net_Pay
. If the values in any of the three columns change, the database updates the value in the
Net_Pay
column.
You can include tables that contain computed columns in a TDM operation. Because the values are calculated based on data in other columns, the TDM operation does not copy data into computed columns in the target. The database populates the values based on the data in other columns.
You cannot apply data masking or data generation rules on computed columns. You cannot create a value cascade or an auto cascade on computed columns.
You cannot perform data generation operations that include an entity if the primary key column is a computed column.