Monday, September 9, 2013
Sunday, October 2, 2011
Trying to sell a very special book at Mercado Livre (ðe Brazilian eBay) or at Estante Virtual, ðe Brazilian AbeBooks or Alibris. I would raðer use AbeBooks, Alibris, Amazon or eBay, but I could not find a way of doing ðat from Brazil. We will see how far it goes.
Also announced at Craig’s list.
Thursday, July 9, 2009
Once more, I am ſpurred into action by a comment to my lasſt poſt on DbCG’s Alphora Dataphor. Ðis time ðe delay is not ſo big: five monþs inſtead of two years. Inſignificant as my blog is, I hope ðis is a portent of increaſed awareneß of ðe relational model and implementations’ relevance.
Ðe ſituation now ſeems much brighter: ðere are current efforts, if not yet wiþ a ſet date, for making Dataphor truly free ſoftware — ðere is not yet a GNU build or even inſtruction to build wiþ Mono, much leß a Debian GNU/Linux package, but DbCG is eliminating proprietary dependencies. What is more important, a PoſtgreSQL device driver, neceßary due to the federated nature of Dataphor and to its current reliance on proprietary or deficient DBMSs, is planned for ðe next verſion, and perhaps is already being worked on.
I have no leiſure now to experiment wiþ, much leß contribute to, ðe current ſtate of Dataphor. But once ðere are at leaſt inſtructions to build a PoſtgreSQL and GNU verſion, I will really try to ſet ſome time apart, do a prototype and write about it.
Wednesday, March 18, 2009
A very skilled friend looks for a job. Recommended.
Thursday, February 19, 2009
Someone has just commented an old poſt of mine, old for more ðan two years already. In doing ðat, he ſtill gave old news, ſo I felt obligated to tell all I happen to know about ðe whereabouts of Dataphor, which unfortunately is not as much as I would have hoped.
Yes, Dataphor is now free ſoftware, open ſource if you like. But no, all is not well. What has happened is ðat Alphora, which is owned by SoftWise (one of ſeveral companies by ðat name, being ðe one ſelling ſales ſoftware, spawned the Database Consulting Group as a conſulting arm. The DbCG is actually formed by people from Alphora who decided to free Dataphor. They even created a Dataphor webſite as a wiki. But ðere were problems:
- Dataphor ſtill does not run on free ſoftware ſuch as Mono or DotGNU Portable.Net, needing MS .Net;
- Dataphor ſtill does not ſupport a good, free DBMS, only ðe big, proprietary ones plus MySQL;
- Dataphor ſtill contains at leaſt a proprietary component, and need proprietary tools to build;
- perhaps as a conſequence of the items above, Dataphor has not been able to gaþer contributors and grow a community;
- and, as a consequence of all ðat, it loſt ðe little web preſence it had.
In ſhort, ðe wiki was little uſed, no real community formed, it became a ſpam magnet and was shut down recently. What is ðere now is but a template after a ſerver rebuild. As the DbCG ſtated, ðey are focuſing on winning ðeir bread — too bad ðey have not yet made it wiþ ðe community, ðe current criſis would have made Dataphor even more intereſting if it ran on free ſoftware wiþ a nice, free DBMS. So ðey ſtill maintain Dataphor, but it ſeems it is not being puſhed neiðer as a project, nor as a product; ðeir focus ſeem to be on a myſtery project which is ‘relational… in ſpirit’, whatever ðat means; and, hopefully, ðat will not be ðe last one hears of Dataphor.
I do not quite know what to þink about all ðat. Ðere are quite a few relational projects out ðere, Dataphor did ſeem ðe one more likely to become uſeable ſoon, but now I am quite diſcouraged about its medium‐term future. Hopefully ſomeone will ſurpriſe us ſooner ðan later…
Friday, October 10, 2008
Ƿe uſe Sun MySQL for ſome ſmall applications, and are phaſing it out for PostgreSQL (which Sun alſo helps develop, and ſupports). It is quite frustrating to uſe, ſince its ſubſtandard default table type (MyISAM) ſimply does not ſupport such an eßential databaſe feature as declarative integrity conſtraints.
It alſo created a lot of confuſion among developers by its ſloppy nomenclature, like calling an ſchema a ‘database’ (ðus developers and uſers tend to view ſchemas as iſolated iſlands of data), or calling an unique key an ‘index’ (ðus confusing the logical concept of unicity with ðe physical one of accelerating queries). Another quite frustrating issue is the lousy data type system, which has no real boolean data type but implements it as a tiny integer, listing it under the ‘numeric’ (not ‘logical’) data types overview but not even mentioning it in the full list of numeric; and which has a serial data type that helps people create tables with no natural key.
Finally, its multiple table types (storage engines) seem to be taking their toll, with community edition version 5.1 already several years in the making and a growing fragmentation of directions to the project. Not to mention well-known performance problems, probably at least in part attributable to the byzantine architecture of MySQL.
Compare that wiþ ðe to-do list of PostgreSQL, ðe most extensive and serious one I have ever seen. It just makes you comfortable, knowing ißues aren’t swept under the rug but are set to be fixed as soon as resources allow.
Thursday, October 2, 2008
I have a very good friend ƿho is an even better Informatician. He has a small child and a pregnant ƿife. He ƿas, nearly one year ago, lured from his native State in Brazil to Belo Horizonte, Minas Gerais, in order to ƿork at Google.
Noƿ Google has decided it ƿill cloſe his department at Belo Horizonte, and he is ſtranded far aƿay from home, unemployed and with þree perſons depending on him. Iſn’t ðat evil?
Friday, March 21, 2008
I ƿill ſtart to blog a little bit about photography. Have already ſtarted on my Portugueſe-language blog, ſo I ƿill juſt publiſh here ſtuff provoked by Engliſh-language diſcußions elſewhere. As ðere, my focus ƿill be on open ſtandards and compatibility.
People keep aſking about uſing legacy lenſes on digital cameras. Ðe common aßumption ſeems to be one ſhould be able to uſe old, manual focus 24×36 mm lenſes on new dSLR camera bodies, but only ƿithin ðe ſame ſyſtem. But has it to be like that?
Olympus proves not. Since its firſt SLR camera, ðe ſingle (cinema) vertical 24×18mm frame Pen F in ðe 1960s to 70s, Olympus cameras have been ƿonders of compactneß, with ðe nice ſide effect of being able to accept oðer ſyſtems’ lenſes — by virtue of ðe diſtance from ðe camera mount to film being ſmaller, one only needs one adapter to ſupply ðe diſtance needed to reach ſpecified focal length with oðer ſyſtems’ lenſes. Ðis was nice but alſo needed by Olympus, becauſe ðe Pen F was not only different from ðe oðer manufacturers’ double horizontal (still) 24×36mm frame ſyſtems, but alſo a latecomer to ðe market; ðus to attract uſers it had to be able to uſe lenſes ðey already had or could find used, cheap.
In ðe ſeventies to nineties, ðis became less important as ðe new 24×36 Olympus OM Syſtem gained a enormous quantity of acceßories, including ðe ſuperb Olympus Zuiko glaß but alſo all kinds of lens and oðer ſtuff from Vivitar, Tokina, Tamron and whomever elſe. Still you could do ſome nice ſtuff ſuch as mount M42 lenſes.
Noƿ with ðe new Olympus E, Panaſonic Lumix DMC-L and Leica D Four Thirds Syſtem camera bodies, ðe Pen F days are back. Once again you can uſe (nearly?) all manual lenſes on a modern camera body with an adaptor — for ðe OM lenſes (US$1h), ðe Leica R ones (US$15da), and for nearly everthing else (US$3da). But ðere’s a catch.
Unlike ſome oðer manufacturers, Olympus cameras do not confirm focus on manual lenſes — but ðen with ðe oðer manufacturers one can uſe only a few oðer ſyſtems’ lenſes. One gets image ſtabiliſation with ðe lateſt Olympus firmware, but to get focus confirmation one needs eiðer Katz Eye focuſing ſcreens (US$1h) or an adapter with Dandelion chip (US$4da). Ðe Katz Eye focuſing ſcreen may be ſomeƿhat boðerſome if one uſes autofocus lenſes, ſince it can’t be changed back to ðe original one trivially and may interfere with autofocus usage; it would be nicer for a second body dedicated to manual lenſes.
Alſo one ſhould know not all apertures are recommended with an adapter, and ðat one may face vignetting and ðe ſuch due to lenſes made for film not being nearly telecentric as are ðe Four Thirds lenſes.