A Condensed 35-Year History of DB2 for z/OS (...and Db2 for z/OS)

Let's go back in time... over three decades ago... back to the wild and woolly 1980s! And watch our favorite DBMS, DB2, grow up over time.

DB2 Version 1 Release 1 was announced on June 7, 1983, and it became generally available on Tuesday, April 2, 1985. I wonder if it was ready on April 1st but not released because of April Fool’s Day? Initial DB2 development focused on the basics of making a relational DBMS work. Early releases of DB2 were viewed by many as an “information center” DBMS, not for production workloads, like IMS was.

Version 1 Release 2 was announced on February 4, 1986 and was released for general availability a month later on March 7, 1986. Can you imagine waiting only a month for a new release of DB2 these days? But that is how it happened back then. Same thing for Version 1 Release 3, which was announced on May 19, 1987 and became GA on June 26, 1987. DB2 V1R3 saw the introduction of DATE data types.

You might notice that IBM delivered “releases” of DB2 back in the 1980s, whereas today (and ever since V3) there have only been versions. Versions are major changes, whereas releases are not quite as significant as a version.

Version 2 Release 1 was announced in April 1988 and delivered in September 1988. Here we start to see the gap widening again between announcement and delivery. V2R1 was a significant release in the history of DB2, a bellwether of sorts for when DB2 began to be viewed as capable of supporting mission-critical, transaction processing workloads. Not only did V2R1 provide significant performance enhancements but it also signaled the introduction of declarative Referential Integrity (RI) constraints.

No sooner than V2R1 became GA than IBM announced Version 2 Release 2 on October 4, 1988. But it was not until a year later that it became generally available on September 23, 1988. DB2 V2R2 again bolstered performance in many ways. It also saw the introduction of distributed database support (private protocol) across MVS systems.

Version 2 Release 3 was announced on September 5, 1990, and became generally available on October 25, 1991. Two very significant features were added in V2R3: segmented table spaces and packages. Segmented table spaces quickly became a de facto standard and packages made DB2 application programs easier to support. DB2 V2R3 is also the version that beefed up distributed support with Distributed Relational Database Architecture (DRDA).

Along comes DB2 Version 3, announced in November 1993 and GA in December 1993. Now it may look like things sped up again here, but not really. This is when the early support program for DB2 started. Early support was announced in March 1993 and delivered to customers in June 1993. V3 greatly expanded the number of buffer pool options available (from 5 pools to 80), and many advances were made for DB2 to take better advantage of the System 390 environment, including support for hardware-assisted compression and hiperpools. It was also V3 that introduced I/O parallelism for the first time.

Version 4 signaled another significant milestone in the history of DB2. It was highlighted by the introduction of Type 2 indexes, which removed the need to lock index pages (or subpages, now obsolete). Prior to V4, index locking was a particularly thorny performance problem that vexed many shops. Data Sharing made its debut in V4, too, and with it, DB2 achieved new heights of scalability and availability allowing users to upgrade without an outage and to add new subsystems to a group “on the fly.” DB2 V4 also introduced stored procedures, as well as CP parallelism.

In June 1997 DB2 Version 5 became generally available. It was the first DB2 version to be referred to as DB2 for OS/390 (previously it was DB2 for MVS). Not as significant as V4, we see the trend of even-numbered releases being bigger and more significant than odd-numbered releases (of course, that is just my opinion). V5 was touted by IBM as the e-business and BI version. It included Sysplex parallelism, prepared statement caching, reoptimization, online REORG, and conformance to the SQL-92 standard.

Version 6 brings us to 1999 and the introduction of the Universal Database term to the DB2 moniker. The “official” name of the product became DB2 Universal Database for OS/390. And the Release Guide swelled to over 600 pages! Six categories of improvements were introduced with V6 spanning object-relational extensions, network computing, performance and availability, capacity improvements, data sharing enhancements, and user productivity. The biggest of the new features were SQLJ, inline statistics, triggers, large objects (LOBs), user-defined functions, and distinct types.

Version 6 is also somewhat unique in that there was this “thing” typically referred to as the V6 refresh. It added functionality to DB2 without there being a new release or version. The new functionality in the refresh included SAVEPOINTs, identity columns, declared temporary tables, and performance enhancements (including star join).

March 2001 brings us to DB2 Version 7, another “smaller” version of DB2. Developed and released around the time of the Year 2000 hubbub, it offered much-improved utilities and some nice new SQL functionality including scrollable cursors, limited FETCH, and row expressions. Unicode support was also introduced in Db2 V7.

DB2 Version 8 followed, but not immediately. IBM took advantage of Y2K and the general desire of shops to avoid change during this period to take its time and deliver the most significant and feature-laden version of DB2 ever. V8 had more new lines of code than DB2 V1R1 had total lines of code!

With DB2 9 for z/OS, we drop the “V” from the name. Is that in response to Oracle’s naming conventions? Well, we do add a space between the DB2 and the version number because we don’t want to talk about DB-twenty-nine! A lot of great new functionality comes with DB2 9 including additional database definition on demand capabilities, binary data types, and a lot of new SQL capabilities including OLAP functions and EXCEPT/INTERSECT. But probably the biggest new feature is pureXML, which allows you to store DB2 data as native XML. The XML is stored natively as a new data type that can be searched and analyzed without the need to reformat it. The approach was novel in that it  supports native XML, basically enabling dual storage engines.

And that brings us to DB2 10 for z/OS. This version of DB2 was built to take advantage of many zEnterprise (the latest new mainframe at the time) features to deliver scalability. Examples include improved compression, cache optimization, blades for running the Smart Analytics Optimizer, etc. 

Additional capabilities included many performance improvements (BIND, IN-list, utilities, etc.), hash organized table spaces, high-performance DBATs (DDF threads) forced to use RELEASE COMMIT, parallel index updating, efficient caching of dynamic SQL with literals, temporal data support, safe query optimization, improved access path hints, access to currently committed data, new TIMESTAMP precision and time zones, and buffer pool options for pinning objects in memory.

In October 2013 we got another new version, DB2 11 for z/OS. Click on that link if you want all the details, but some highlights included transparent archiving, global variables, improved SQL PL, APREUSE(WARN), significant utility improvements, DROP COLUMN support, and JSON support with IBM BigInsights.

And that brings us to the present day, with DB2 12 for z/OS as the current (and soon to be only) supported version of Db2. Released for general availability in October 2016, DB2 12 for z/OS abandons the traditional new release cycle that IBM has followed for decades, adopting a new continuous delivery model. New functionality is now delivered in Function Levels (FLs) that are easily applied and delivered much more rapidly than in the past. Indeed, the current Db2 function level is FL506, which means there have been 6 new function levels added since 2016.

Version 12 brought with it a plethora of new capabilities including virtual storage enhancements, optimization improvements, and improved control over the introduction of new SQL capabilities. DB2 12 for z/OS delivered many improvements for both application development and database administration. Examples of new application capabilities include:

• Additional support for triggers, arrays, global variables, pureXML, and JSON
• MERGE statement enhancements
• SQL pagination support
• Support for Unicode columns in an EBCDIC table
• Piece-wise deletion of data
• Support for temporal referential constraint
• More flexibility in defining application periods for temporal tables
• PERCENTILE function support
• Resource limits for static SQL statements
• Db2 REST services improve efficiency and security
• DevOps with Db2: Automated deployment of applications with IBM UrbanCode Deploy

Examples of new DBA and SYSADM capabilities include:

• Installation or migration without requiring SYSADM
• Improved availability when altering index compression
• Online schema enhancements
• Improved catalog availability
• Object ownership transfer
• Improved data validation after running DSN1COPY
• Automatic start of profiles at Db2 start
• Increased partition sizes and simplified partition management for partition-by-range table spaces with relative page numbering
• Ability to add partitions between existing logical partitions
• UNLOAD privilege for the UNLOAD utility
• Temporal versioning for Db2 catalog tables
• Statistics collection enhancements for SQL performance    

Of course, these are just some of the V12 improvements; there are many more (as well as all of the Function Level improvements)!

Then sometime in the middle of 2017, IBM decided to change the name of DB2 by making the uppercase B a lowercase b. So now the name of our beloved DBMS is Db2. Nobody has been able to explain to me what the benefit of this was, so don’t ask me!

The Bottom Line

I worked with DB2 way back in its Version 1 days, and I’ve enjoyed watching DB2 grow over its first 35 years. Of course, we did not cover every new feature and capability of each version and release, only the highlights. Perhaps this journey back through time will help you to remember when you jumped on board with Db2 and relational database technology. I am happy to have been associated with Db2 (and DB2) for its first 35 years and I look forward to many more years of working with Db2… 

IBM Announces DB2 10 for z/OS Beta Program

IBM announced the beta program for the next version of DB2 today, now "officially" known as DB2 10 (no more DB2 X). It is a closed beta program that will begin on March 12, 2010. That means you have to be selected by IBM to participate.

The announcement highlighted some of the areas of improvement to be delivered by DB2 10 for z/OS, and at the top of that list, to no one's surprise, is performance. DB2 10 promises to deliver out-of-the-box savings by improving operational efficiencies ranging from 5% to 10% out-of-the-box CPU savings for traditional workloads and up to 20% out-of-the-box CPU savings for nontraditional workloads.

Other areas called out by IBM in the announcement include

• Improved business resiliency through scalability improvements and fewer outages (planned or unplanned).
• Schema evolution or data definition on demand as well as query performance manageability enhancements support improved availability.
• New features such as hash access, index include columns, inline large objects, parallel index updates, faster single row retrievals, work file in-memory, index list prefetch, 64-bit memory enhancements, use of the 1 MB page size of the System z10, buffer pools in memory, access path enhancements, member clustering for universal table spaces, efficient caching of dynamic SQL statements with literals, improved large object streaming, and SQL procedure language performance.
• Rapid application and warehouse deployment for business growth including improved concurrency for data access, data management, and data definition.
• The ability avoid an outage by adding active log data to a subsystem.
• Improved application and data warehousing support including temporal data, a 64 bit ODBC driver, currerntly committed locking, implicit casting or loose typing, timestamp with time zone, variable timestamp precision, moving sum, and moving average.
• Improvements to DB2's XML support including expanded pureXML, customer-driven performance and usability requirements, schema validation in the engine, binary XML exchange format, multiversioning, easy update of subparts of XML document, stored procedures, user-defined functions and triggers, XML index matching with date/timestamp, and a CHECK XML utility.
• Enhanced query and reporting facilities, including QMF V10 with over 140 new analytical functions, support for HTML, PDF, and Flash reports, and more.

So it would seem that there is a lot of new functionality for us to begin to become acquainted with. As IBM rolls out more details, and customers begin to use the new version of DB2, we will examine some of these new features in more depth here on the DB2 Portal blog.

If you are interested in the beta program, the pre-requisite for DB2 10 is z/OS V1.10 (5694-A01) or later running in 64 bit mode. More information about the DB2 10 beta program is available on IBM's web site.

No GA date for DB2 10 has been announced.

Deprecated Features Planned for DB2 X for z/OS

Everyone is always interested in the latest and greatest features of their favorite DBMS, in this case DB2. But sometimes features get removed from the DBMS when a new version is released. According to the IBM teleconference on DB2 X for z/OS today, there are several features planned to be deprecated (i.e. removed). Let's briefly take a look at them.

The first feature that will be removed is private protocol DRDA. This should come as no surprise to anybody since IBM has been indicating that private protocal distribution was on its way out for a number of releases now. And it really is not that difficult to convert to DRDA (and there will be some new help in DSNTP2DP).

Perhaps more troublesome to some shops will be the removal of support for plans containing DBRMs. You will have to convert the DBRMs to packages when you get to DB2 X. You would think that since packages have been available as far back as V2.3 that most shops would have converted to them already. But I do know that there are some shops out there" who still have DBRMs bound directly into their plans. So start planning to convert ASAP! IBM will offer some support in DB2 X to track down affected plans.

While on the topic of plans and packages, you will have to REBIND any that have not been rebound since V5 or before. But it is a good rule to REBIND everything when you go to a new version of DB2 anyway, and most (but not all) shops do that.

From a documentation perspective, BookManager will no longer be supported. Instead we get the PDF versions and the Info Center online.

And the DB2 Management Clients (DB2 Administration Server, Control Center, and Development Center) are deprecated. IBM's new management client direction for DB2 is Data Studio.

Other deprecated items include:

• ACQUIRE(ALLOCATE) [change to ACQUIRE(USE)]
• Workload capture through profile monitor
• XML Extender [change to use pureXML data type]
• DB2 MQ XML user-defined functions and stored procedures [change to XML functions]
• msys for Setup DB2 Customization Center [change to install panels]

At this point, DB2 X is on track to become generally available at the end of next year, 2010. At this point IBM has announced that migration will be supported from DB2 9 NFM (and has hinted that they are considering supporting migration to DB2 X directly from DB2 V8 NFM).

IBM IOD2009 Day One

It is Monday, October 26, 2009, and the annual IBM Information on Demand (IOD2009) conference is officially underway. Well, actually it kicked off with a bang on Sunday. The exhibition hall opened at 6:00 pm and the early goers traipsed through the vendor hall sharing stories, checking out the vnedor's wares, and looking for the latest tschotskes (the favorites seem to be a mini-book light being given out by SPSS and the nifty DB2 t-shirts being given out by SEGUS, Inc.).

But the event really does not get started (at least as far as I'm concerned) until the big Monday morning kickoff, which this year was emceed by Terry Fator (the ventriloquist impersonator who won America's Got Talent) last year. He did a very nice job, and his mimicry and ventriloquism skills are great... but I think ventriloquism works better in a more intimate setting.

Before Terry came on an IBMer shared several tidbits of data from research and from polls they have been taking at IOD. For example, did you know that 15 petabytes of data are created every day? Regarding the even, they shared that there are more overall attendees here than there were at last year's event (6,000+) and that the average distance folks traveled to attend #IOD2009 is 2500 miles. You can actually participate in the daily IOD polls at http://iodpoll.com.

In between the entertainment respites, we got to hear from several IBM folks, including Ambuj Goyal, Arvind Krishna, and Frank Kern. According to Mr. Goyal, IBM is building an information on demand software stack to deliver trusted information. This can solve a very real problem that organizations are experiencing today. You see, it seems that one in three business leaders frequently make critical decisions based on inaccurate or non-existing information. Business executives don't just need data, but trusted information that can be relied upon for analysis to make accurate business decisions.

Again, according to Goyal, he sees IBM's Information Agenda doing for trusted information what ERP did for enterprise resource processes. IBM will help move its customers from information projects to information-based architecture and operations, moving organizations from information on demand to information transformation.

Then Frank Kern hosted three IBM customers as he asked each of them to explain how they benefited from IBM's Information Management solutions. The representative from BlueCross BlueShield talked about their data warehouse with 54 millions records, which happens to be the largest healthcare data warehouse in the world. Their analytical data is made available thru a portal. Offering integrated healthcare details helps improve healthcare. And the Chevron representative spoke about how IBM has helped Chevron improve its supply chain operations using integrated information.

And Arvind Krishna, GM of the Information Management group at IBM, told about IBM's on-going investments in research and development for IOD. So far, IBM has invested over $12 billion in R+D and acquisitions.

IBM also unveiled some announcements today at IOD including several new offerings to provide organizations with analytics capabilities to make better use of their archived information and improve business processes. These offerings are part of IBM's unified archiving strategy called IBM Smart Archive. Most intriguing to me is the preview of a SaaS offering called IBM Information Archive Cloud Services. The entire press release can be read here, if you're interested in the topic.

I also attended a presentation on DB2 X which was quite interesting, too. Delivered by Jeff Josten, there was much good news for mainframe DB2 folks including improved performance, temporal support, improved utility operations, hashed data and access paths, and more. I tweeted about this quite extensively on Twitter.

In fact, if you want to follow my tweets all week (well, thru Wednesday) be sure to follow me on Twitter at http://www.twitter.com/craigmullins... even when I'm not at a conference like IOD, I regularly tweet on DB2, database, and information management topics.

Hear Ye, Hear Ye, Learn All About DB2 X for z/OS

IBM is hosting a free webinar on November 3, 2009, offering a technical preview of the next version of DB2 for z/OS, currently known as DB2 X (but we all know, err, ah, think it will be called DB2 10).

If you work with DB2 on the mainframe you will want to set aside some time to attend this informative DB2 X webinar. It will have information for DBAs, as well as for Managers, Application Architects, Developers, System Administrators, System Programmers, and System Architects... and that is just about anyone who works with DB2.

The speaker will be IBM Distinguished Engineer, Jeff Josten.

How do you participate, you may be asking? Well, that is easy. Simply click on over to DB2 X for z/OS Technical Preview and register yourself.

The webinar will be held on November 3, 2009 at 11:00 a.m. Eastern Standard Time, 4:00 p.m. UTC.