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Db2 13 GA function levels preview

By Paul McWilliams posted Mon July 18, 2022 10:28 PM


Db2 13 continues and evolves the migration and continuous delivery approaches that were first introduced in Db2 12, where function levels (FLs) control the introduction of new capabilities.

Db2 13 starts with three function levels at migration: FL 100, FL 500, and FL 501, instead of the two available in Db2 12 at general availability (GA). 

Adding FL 501 to the migration process improves and simplifies Db2 13 migration processing, enables you to decide when you are ready to make the first Db2 13 catalog changes, and delays the catalog changes until release coexistence with Db2 12 and fallback are no longer a concern. For more about that, see our recent blog entry: Get ready for migration to Db2 13.

New Db2 13 installations start with FL 501 activated.

My focus for this entry is a preview of the new-function content available in the Db2 13 GA function levels. Also, keep in mind that we started continuous delivery in Db2 13 from day one, so new-function APARs and more function levels are coming soon!

What’s in the Db2 13 function levels at GA?

You might sometimes hear that “most new function” is only available only after you activate FL 500 or higher in Db2 13. However, it really depends on how you look at it. If you are considering only new application and SQL capabilities, then most of those do remain unavailable until you activate FL 500 or higher—and indeed until you run the applications at the higher application compatibility (APPLCOMPAT) level.

However, if you consider all new function in Db2 13, quite a lot of it becomes available immediately in FL 100! Let’s look at what’s available in each of the three Db2 13  GA function levels.

Function level V13R1M100 (FL 100)

Db2 13 is at FL 100 as soon as you start Db2 on the new release, and quite a lot of the enhancements in Db2 13 are already available. Many of them provide benefit with little to no external changes. That is, many don’t change how you install, configure, or use Db2.

If we consider the number of documented new-function items available in the Db2 13 GA function levels, FL 100 has the most with 25. You can read more about each of these items in the documentation topic for FL 100 and we’ll cover many in future blog entries, but here are the headlines for  FL 100:

  • Index look-aside optimization
  • Sort optimization
  • Expanded SORTL usage with learning from execution (IBM® z15™)
  • Improved locking for INSERT to partition-by-growth (PBG) table spaces
  • Reduced ECSA storage for IFI buffers (part 2)
  • Reduced agent local below-the-bar (BTB) storage
  • DBAT availability improvements
  • Improved performance when using external security
  • Reduced ECSA storage use for distributed data facility (DDF) processing
  • Improved storage monitoring and contraction
  • Improved Db2 installation and migration process for customizing the amount of private storage for IRLM locks
  • Reduced memory usage for REBIND with APREUSE
  • Partition range support in IFCID 306 for users of replication applications
  • EDITPROC support in IFCID 306 for users of nonproxy mode replication applications
  • Relative page numbering for new PBR table spaces
  • Improved default statistics collection granularity
  • REPAIR utility WRITELOG for decompression dictionaries
  • Enhanced space-level recovery with the RECOVER utility
  • Column names longer than 30 bytes
  • Db2 support for z/OS continuous compliance
  • More concurrent open data sets with z/OS 2.5
  • More efficient cleanup for above-the-bar storage
  • Index page split instrumentation enhancements
  • Accounting information on the longest wait times for common suspension types
  • IBM z16 group buffer pool (GBP) residency time
  • Subsystem parameter simplification

As an aside, you might be curious about the order of these items, and why your favorites are far down the list. As a technical writer, I insist that a bullet list has no semantic order! However, if you must know, we used the internal tracking numbers for these items to order them.

Function level V13R1M500 (FL 500)

As in Db2 12, activation of FL 500 in Db2 13 prevents fallback to Db2 12 and coexistence with members on the prior release in data sharing.  FL 500 is again the earliest that most new application and SQL capabilities can be used, including new DDL capabilities. You can read more about these items in the documentation topic for FL 500, but here are the headlines for the new-function items in FL 500:

  • Increased flexibility for package ownership
  • Page sampling for inline statistics
  • SQL Data Insights
  • Reduced ECSA storage for IFI buffers (part 1)
  • Online conversion of tables from growth-based (PBG) to range-based (PBR) partitions
  • Fast index traversal (FTB) support for larger index keys
  • Increased control for applications over how long to wait for a lock
  • Profile table enhancements for application environment settings
  • Ability to delete an active log data set from the BSDS while Db2 is running
  • SPT01 and SYSLGRNX table spaces are converted to DSSIZE 256 GB
  • Improved concurrency for altering tables for DATA CAPTURE
  • Change REORG INDEX SHRLEVEL REFERENCE or CHANGE so the NOSYSUT1 keyword is the default


Function level V13R1M501 (FL 501)

The new capabilities that require changes to the structure of Db2 catalog objects remain unavailable until you activate FL 501 or higher. In terms of quantity, it’s a small number of items, but it includes some popular heavy hitters, such as the foundation for the new utility history capabilities. And of course, you can read more about these items in the documentation topic for FL 501.

Here is the list of headlines for new-function items in FL 501:

  • Allow applications to specify a deadlock resolution priority
  • Profile table enhancements for application environment settings
  • Real-time statistics scalability
  • Collection of real-time and historical information about utility execution
  • Real-time statistics support for index splits

Be sure to subscribe and stay tuned to this blog for more entries about the exciting new capabilities in Db2 13!

In the meantime, also consider checking out the IBM Redbooks publication Db2 13 for z/OS and More for a deeper dive into the new capabilities of Db2 13.