Discussion of the TransRelational data model, chiefly advocated by Chris Date and his followers, now that creator Required Technologies is more or less defunct. Posts have focused on whether the TransRelational model will ever see the light of day in a commercially useful product.
I just put up a long post about a small development-stage company, ScaleDB. The punchline is that ScaleDB has a data access method — an extension of Patricia tries — that gives referential integrity and updatable views for free.
People who think current “relational” DBMS aren’t relational enough often suggest that’s the kind of foundation DBMS should have. And unlike Required Technologies’ TransRelational (TM) shtick, ScaleDB’s really is an OLTP-oriented approach.
In the first “meat” — i.e., other than housekeeping — post on the new Database Column blog, Mike Stonebraker makes three core claims:
1. Different DBMS should be used for different purposes. I am in violent agreement with that point, which is indeed a major theme of this blog.
2. Vertica’s software is 50X faster than anything non-columnar and 10X faster than anything columnar. Now, some of these stats surely come from the syndrome of comparing the future release of your product, as tuned by world’s greatest experts on it who also hope to get rich on their stock options in your company, vs. some well-established production release of your competitors’ products, tuned to an unknown level of excellence,* with the whole thing running test queries that you, in your impartial wisdom, deem representative of user needs. Or something like that … Read more
|Categories: Benchmarks and POCs, Columnar database management, Data warehousing, Database diversity, Michael Stonebraker, OLTP, Theory and architecture, TransRelational||3 Comments|
The best known columnar RDBMS is surely Sybase’s IQ Accelerator, evolved from a product acquired in the mid-1990s. Problem – it doesn’t have a shared-nothing architecture of the sort needed to exploit grid/blade technology. Whoops. The other recognized player is SAND, but I don’t know a lot about them. Based on their website, it would seem that grids and compression play a big part in their story. Less established but pretty interesting is Kognitio, who are just beginning to make marketing noise outside the UK. SAP’s BI Accelerator is also a compressed columnar system, but operates entirely in-memory and hence is limited in possible database size. Mike Stonebraker’s startup Vertica is of course the new kid on the block, and there are other columnar startups as well whose names currently escape me.
|Categories: Data warehousing, Investment research and trading, Kognitio, SAP AG, TransRelational||3 Comments|
A lot of evidence is pointing to a major paradigm shift in data warehouse RDBMS, along the lines of:
Old way: Assume I/O is random; lower total execution time by improving selectivity and thus lowering the amount of I/O.
New way: Drive the amount of random I/O to near zero, and do as much sequential I/O as necessary to achieve this goal.
- Data warehouse appliances (see especially this discussion of DATallegro’s architecture)
- Columnar systems (see Nathan Myer’s first comment in this discussion of the much-hyped Required Technologies prototype)
- Memory-centric systems, notably SAP’s BI Accelerator
|Categories: Data warehouse appliances, DATAllegro, Memory-centric data management, SAP AG, Theory and architecture, TransRelational||4 Comments|
This was back in November 2004, and doesn’t say anything I haven’t also said here, but I’m glad to see that a few other people had the guts to call a jerk a jerk and to at least raise doubts about some very dubious behavior.
That said, if you aren’t amused by flame wars, it’s probably not worth the trouble to read.
There’s a vigorous discussion of TransRelational over on Alf Pedersen’s blog (Edit: Link died), although it’s completely polluted by some usual-suspects flame war BS.
Alf did poke through the dreck, however, to make a reasonable challenge, which can be paraphrased as:
OK. Suppose you’re right that no implementation has ever provided evidence of TransRelational’s usefulness for building a True Relational DBMS. It’s still theoretically fascinating.
My response was as follows:
Here are two big problems with TransRelational that are perfectly theoretical.
First, it assumes that values can be concisely stated, presumably as numbers or character strings. That isn’t a good match to complex datatypes such as, say, documents that should be full-text indexed.
Second, it assumes that there’s a natural sort order. That could be a bit of a problem even for, say, geospatial. One would think there’s a workaround in the geospatial case, e.g. like Oracle’s old hhencode. But hhencode was a fiasco, I think because it didn’t actually measure proximity very effectively.
Admittedly, both of my objections also apply to good old b-trees. Still, they speak against the potential of a TransRelational implementation to achieve the kind of generality I think modern applications do and will increasingly demand.
Basically, I think a “True Relational” DBMS that was only useful for columns with natural sort orders wouldn’t be particularly interesting. And “The Third Manifesto” notwithstanding, that’s the only kind anybody seems to have even hinted at trying to bring to market.
In prior posts, I’ve mentioned the essential dishonesty behind the hoohah around Transrelational(TM) technology from Required Technologies, Inc., and Chris Date’s highly regrettable promotion of same. Now I’ve been able to get more detail from another former executive of the company. Unsurprisingly, it corroborates what I wrote before, and utterly contradicts some of the myths spread by Date and his acolytes. This executive, while requesting that his name be withheld because of the acrimony between the CEO and just about every other company insider, otherwise gave me permission to report fully on what he told me. Read more
Chris Date is quite annoyed with me, and has taken issue with various things I’ve written. Some of his reasoning is hard to follow. For example, he said something to the effect that it would be silly for him to ever say anything misleading, because he’d immediately be caught out. Uh, Chris – you’re the guy who’s berating the terrible level of education and understanding in a field for which YOU WROTE THE DEFINITIVE TEXTBOOK (which has sold “over 700,000 copies”). If your readers can’t even understand the correct things you say in your book, why should they be able to instantly spot the errors? Read more
Database guru Christopher J. Date is apparently accepting money from attendees to his seminars on TransRelational(TM) database archicture, so that he can tell them about an as-yet unreleased product from Required Technologies, Inc.
This is regrettable on multiple levels.
1. Required Technologies shut down product development in 2002, after running through $30 million; there’s great acrimony between investors and the CEO; and lawsuits are likely.
2. Required’s product never did most of what Date seems to be claiming it now does. It was a read-oriented columnar data store, much like Sybase IQ or a number of other products from younger companies. Read more