Teradata
Analysis of data warehousing giant Teradata. Related subjects include:
Teradata SQL-H, using HCatalog
When I grumbled about the conference-related rush of Hadoop announcements, one example of many was Teradata Aster’s SQL-H. Still, it’s an interesting idea, and a good hook for my first shot at writing about HCatalog. Indeed, other than the Talend integration bundled into Hortonworks’ HDP 1, Teradata SQL-H is the first real use of HCatalog I’m aware of.
The Teradata SQL-H idea is:
- Register your Hadoop data to HCatalog. I’ll confess to being unclear about the details of how that works, for example in the case of data that just doesn’t fit well into flat relational tables. Stay tuned for future posts. For now, I’ll just note that:
- HCatalog is closely based on Hive’s metadata management. If you’ve run Hive against the data, HCatalog should already know about it.
- HCatalog can handle Pig and HBase data as well.
- Write SQL DDL (Data Description Language) so that your Aster cluster knows about the data.
- Write any Teradata Aster SQL/MR against that data. Some of the execution will be done on the Hadoop cluster, but pulling data back into Aster may well be necessary.
At least in theory, Teradata SQL-H lets you use a full set of analytic tools against your Hadoop data, with little limitation except price and/or performance. Teradata thinks the performance of all this can be much better than if you just use Hadoop (35X was mentioned in one particularly favorable example), but perhaps much worse than if you just copy/extract the data to an Aster cluster in the first place.
So what might the use cases be for something like SQL-H? Offhand, I’d say:
- SQL-H use cases are probably focused in areas where copying the data to Aster in advance doesn’t make a lot of sense. So presumably …
- … the Hadoop clusters involved would hold a lot more data than you’d want to pay for storing in Teradata Aster. E.g., think of cases where Hadoop is used as a big bit bucket or archival data store.
- There could be a kind of investigative workflow. First you play around with the Hadoop data via SQL-H. Then when you think you’re onto something, you set up ETL (Extract/Transform/Load) to get the data into Aster and ratchet up the effort.
By way of contrast, the whole thing makes less sense for dashboarding kinds of uses, unless the dashboard users are very patient when they want to drill down.
Thoughts on “data science”
Teradata is paying me to join a panel on “data science” in downtown Boston, Tuesday May 22, at 3:00 pm. A planning phone call led me to jot down a few notes on the subject, which I’m herewith adapting into a blog post.
For starters, I have some concerns about the concepts of data science and data scientist. Too often, the term “data scientist” is used to suggest that one person needs to have strong skills both in analytics and in data management. But in reality, splitting those roles makes perfect sense. Further:
- It may or may not make sense to say that a computer scientist is doing “science”; the term “data scientist” inherits that ambiguity.
- It may or may not make sense to say that a corporate scientist is doing “science”; for example, a petroleum geologist might do very valuable work without making any scientific discoveries. The term “data scientist” inherits that ambiguity too.
- Too often, people use the term big data as if it were something radically new, rather than a continuation of what has been done in large-scale analytic data management for decades. “Data science” has a similar problem.
- The term “data science” sounds as if you need specialized academic training to do it, which isn’t really true.
The leader in raising these issues is probably Neil Raden.
But there’s one respect in which I think the term “data science” is highly appropriate. In conventional science, gathering data is just as much of an accomplishment as analyzing it. Indeed, most Nobel Prizes are given for experimental results. Similarly, if you’re doing data science, you should be thinking hard about how to corral ever more useful data. Techniques include but are not limited to:
- Keeping data you used to throw away. This has driven a lot of growth in relational data warehouses and big bit buckets alike.
- Bribing customers and prospects. Loyalty cards are the paradigmatic example.
- Split testing. The more internet-based users you have, the more tests you can do.
- Storing derived data. That can be as simple as pre-computing the scores from your predictive analytics model, or it can be as complex as running a 50-step sequence of Hadoop jobs.
- Getting data from third parties, for example:
- Supply chain partners (right now this rarely amounts to more than simple BI, but that could change in the future).
- Data vendors of various kinds (e.g. credit bureaus).
- Social media/the internet in general, which also usually involves some kind of service provider.
| Categories: Analytic technologies, Data warehousing, Predictive modeling and advanced analytics, Teradata | 4 Comments |
Our clients, and where they are located
From time to time, I disclose our vendor client lists. Another iteration is below, the first since a little over a year ago. To be clear:
- This is a list of Monash Advantage members.
- All our vendor clients are Monash Advantage members, unless …
- … we work with them primarily in their capacity as technology users. (A large fraction of our user clients happen to be SaaS vendors.)
- We do not usually disclose our user clients.
- We do not usually disclose our venture capital clients, nor those who invest in publicly-traded securities.
- Excluded from this round of disclosure is one vendor I have never written about.
- Included in this round of disclosure is one client paying for services partly in stock. All our other clients are cash-only.
For reasons explained below, I’ll group the clients geographically. Obviously, companies often have multiple locations, but this is approximately how it works from the standpoint of their interactions with me. Read more
Juggling analytic databases
I’d like to survey a few related ideas:
- Enterprises should each have a variety of different analytic data stores.
- Vendors — especially but not only IBM and Teradata — are acknowledging and marketing around the point that enterprises should each have a number of different analytic data stores.
- In addition to having multiple analytic data management technology stacks, it is also desirable to have an agile way to spin out multiple virtual or physical relational data marts using a single RDBMS. Vendors are addressing that need.
- Some observers think that the real essence of analytic data management will be in data integration, not the actual data management.
Here goes. Read more
Hardware and components — lessons from Teradata
I love talking with Carson Schmidt, chief of Teradata’s hardware engineering (among other things), even if I don’t always understand the details of what he’s talking about. It had been way too long since our last chat, so I requested another one. We were joined by Keith Muller, who I presume is pictured here. Takeaways included:
- Teradata performance growth was slow in the early 2000s, but has accelerated since then; Intel gets a lot of the credit (and blame) for that.
- Carson hopes for a performance “discontinuity” with Intel Ivy Bridge.
- Teradata is not afraid to use niche special-purpose chips.
- Teradata’s views can be taken as well-informed endorsements of InfiniBand and SAS 2.0.
| Categories: Data warehouse appliances, Data warehousing, Database compression, Solid-state memory, Storage, Teradata | 13 Comments |
Comments on the analytic DBMS industry and Gartner’s Magic Quadrant for same
This year’s Gartner Magic Quadrant for Data Warehouse Database Management Systems is out.* I shall now comment, just as I did on the 2010, 2009, 2008, 2007, and 2006 Gartner Data Warehouse Database Management System Magic Quadrants, to varying extents. To frame the discussion, let me start by saying:
- In general, I regard Gartner Magic Quadrants as a bad use of good research.
- Illustrating the uselessness of — or at least poor execution on — the overall quadrant metaphor, a large majority of the vendors covered are lined up near the line x = y, each outpacing the one below in both of the quadrant’s dimensions.
- I find fewer specifics to disagree with in this Gartner Magic Quadrant than in previous year’s versions. Two factors jump to mind as possible reasons:
- This year’s Gartner Magic Quadrant for Data Warehouse Database Management Systems is somewhat less ambitious than others; while it gives as much company detail as its predecessors, it doesn’t add as much discussion of overall trends. So there’s less to (potentially) disagree with.
- Merv Adrian is now at Gartner.
- Whatever the problems may be with Gartner’s approach, the whole thing comes out better than do Forrester’s failed imitations.
*As of February, 2012 — and surely for many months thereafter — Teradata is graciously paying for a link to the report.
Specific company comments, roughly in line with Gartner’s rough single-dimensional rank ordering, include: Read more
Terminology: Data mustering
I find myself in need of a word or phrase that means bring data together from various sources so that it’s ready to be used, where the use can be analysis or operations. The first words I thought of were “aggregation” and “collection,” but they both have other meanings in IT. Even “data marshalling” has a specific meaning different from what I want. So instead, I’ll go with data mustering.
I mean for the term “data mustering” to encompass at least three scenarios:
- Integrated (relational) data warehouse.
- Big bit bucket.
- Big bit stream.
Let me explain what I mean by each. Read more
| Categories: Data warehousing, Investment research and trading, Streaming and complex event processing (CEP), Sybase, Teradata | 12 Comments |
Teradata Unity and the idea of active-active data warehouse replication
Teradata is having its annual conference, Teradata Partners, at the same time as Oracle OpenWorld this week. That made it an easy decision for Teradata to preannounce its big news, Teradata Columnar and the rest of Teradata 14. But of course it held some stuff back, notably Teradata Unity, which is the name chosen for replication technology based on Teradata’s Xkoto acquisition.
The core mission of Teradata Unity is asynchronous, near-real-time replication across Teradata systems. The point of “asynchronous” is performance. The point of “near-real-time” is that it Teradata Unity can be used for high availability and disaster recovery, and further can be used to allow real work on HA and DR database copies. Teradata Unity works request-at-a-time, which limits performance somewhat;* Unity has a lock manager that makes sure updates are applied in the same order on all copies, in cases where locks are needed at all.
| Categories: Data warehousing, Teradata | 2 Comments |
Highlights of a busy news week
I put up 14 posts over the past week, so perhaps you haven’t had a chance yet to read them all. 🙂 Highlights included:
- My most important post of the week was a general guide to IT vendor strategy. That one has already spawned discussion at many companies, from the tiny to the multi-billion-dollar.
- The best comment thread of the week was probably on my post about scale-out relational OLTP choices, in which people discussed the merits of various particular alternatives.
- I recommended that people strongly consider attending XLDB 5 in Menlo Park on October 18-19.
Most of the posts, however, were reactions to news events. In particular:
- Teradata announced that Teradata 14 will be hybrid-columnar, more in Vertica’s way than in Greenplum’s or Aster Data’s. (Pay no attention to the Wall Street Journal’s apparent belief that no other analytic DBMS is hybrid-columnar at all.)
- Aster announced the unsurprising news that there will be a Teradata Aster appliance. Also, Aster talked about greater analytic flexibility in the forthcoming Aster 5.0.
- With Oracle OpenWorld coming up, Oracle decided to get some of its announcing out of the way early. In particular, it announced the Oracle Database Appliance, which is small-business-friendly hardware for running the Oracle DBMS. However, the Oracle Database Appliance doesn’t seem to do much about the complexity of running the Oracle DBMS software.
- In a catch-all Hadoop post, I noted that:
- Oracle has now clearly said it has a Hadoop appliance coming, no doubt next week at OpenWorld.
- I still can’t see why Hadoop appliances would succeed, but a lot of smart folks seem to disagree with me.
- Greenplum announced what looks like a nice but unimportant little product upgrade.
- It’s a really good thing that previously reported plans to revamp Hadoop are underway.
- DataStax announced that it really is a Cassandra company after all. Pay no attention to previous marketing that seemed to put DataStax in the same Hadoop-alternative category as, say, MapR.
- Ingres has changed its name to Actian. The announcement seems like a confession that Ingres and VectorWise are going nowhere.
| Categories: Actian and Ingres, Aster Data, Data warehousing, DataStax, Greenplum, Hadoop, Teradata, VectorWise | Leave a Comment |
Workload management and RAM
Closing out my recent round of Teradata-related posts, here’s a little anomaly:
- Teradata is proud that Teradata 14’s workload management now explicitly manages I/O, to go with Teradata’s long-standing management of CPU. Teradata’s WLM still does not explicitly manage RAM.
- Aster is proud that Aster 5’s workload management now explicitly manages RAM, to go along with the WLM capabilities Aster has had for a while managing CPU and I/O. Aster’s Tasso Argyros believes this is an important capability, at least in some edge cases.
- Mike Pilcher of SAND emailed me that SAND’s WLM capabilities to explicitly manage CPU, I/O, and RAM are very well-received by the marketplace.
| Categories: Aster Data, Data warehousing, SAND Technology, Teradata, Workload management | 4 Comments |