DB2 For i Table Function Performance Considerations
March 19, 2014 Michael Sansoterra
In my prior tip, I covered some guidelines on when to use scalar user defined functions (UDF) and the potential performance hit they can impose on a query. In this tip, I’m going to follow up with a few additional guidelines about user defined table functions (UDTFs) in DB2 for i and show how they may impact query performance. Once again, I’m using data from the Microsoft AdventureWorks sample database that has been exported to DB2 for i. Shown below is a sample UDTF named “Transactions” that combines the data from the transaction history and transaction history archive tables: |