August 2015 - Pharo-users - lists.pharo.org

Re: [Pharo-users] Garage, Glorp, PostgreSQL and Cursors

by Esteban A. Maringolo

Garage is a (IMO lousy named) Pharo database interface abstraction, like Perl's DBI, ADODB, or JDBC. Any program that uses Garage's objects to access the database should be abstract enough to enable you to replace the backend by something else without changing the programming logic (e.g. replace PostgreSQL by SQLite). DBXTalk is the same, but at the database driver level, it uses the OpenDBX database drivers. So the relation would be: DB Interface -> DB Adapter -> DB Driver With these possible combinations (among others): Garage -> DBXTalk -> OpenDBX libs (libopendbx.so/dll) Garage -> PostgreSQLv2 -> (written in Smalltalk) Garage -> SQLite -> (written in Smalltalk) The confusion comes also when you add GLORP (ORM) to the combo, which is the most common use case when dealing with RDBMS, with the added misnomer of GLORP calling "Driver" what in practice is an Adapter (pattern) written in Smalltalk . So you have the following GlorpDriver (Adapter) -> DB Interface So: GlorpDBXTalk -> Garage GlorpPostgresV2 -> PostgresV2 GlorpSQLite -> PunQLite The benefits of having an abstraction layer like Garage are many, maybe the misnomer and the lack of coordination provokes this confusion. Regards! -- Esteban A. Maringolo Esteban A. Maringolo 2015-08-03 10:35 GMT-03:00 Sean P. DeNigris <sean(a)clipperadams.com>: > vmusulainen wrote >> http://pharo.org/news/garage-database > > I'm also confused. What is the relationship between OpenDBX and Garage? IIRC > DBXTalk was the previous name of OpenDBX, right? Maybe an FAQ is in order as > the DB-related names seem to be multiplying ;) > > > > ----- > Cheers, > Sean > -- > View this message in context: http://forum.world.st/Garage-Glorp-PostgreSQL-and-Cursors-tp4840760p4840771… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >

Aug. 3, 2015

open street map example

by Alexandre Bergel

Hi! Some of you have an interest in visualizing graphs on top of open street maps. Together with Hilaire we made a small example: -=-=-=-=-=-=-=-=-=-=-=-= | v map data b d whiteBackground london elementsAndEdges | v := RTView new. v @ RTDraggableView. map := RTOSM new. v add: map element. "Place to set the data and center the camera" london := 51.507222@ -0.1275. "Some arbitrary data" data := ((1 to: 500) collect: [ :i | 50 atRandom - 25 ]) cumsum. "We build the graph" b := RTGrapher new. b extent: 100@30. d := RTData new. d noDot. d connectColor: Color red. d points: data. b add: d. b axisY labelFontHeight: 6; color: Color red; title: 'Sale'. b axisX color: Color red; noTick; title: 'country'. b build. elementsAndEdges := b view elements, b view edges. "We create a white background" whiteBackground := (RTRoundedBox new color: Color white trans; borderRadius: 10) element. v add: whiteBackground. v addAll: elementsAndEdges. RTNest new on: whiteBackground nest: elementsAndEdges. whiteBackground translateTo: (map latLonToRoassal: london). v canvas camera translateTo: (map latLonToRoassal: london). v canvas camera noInitializationWhenOpen. v canvas camera scale: 1.5. v -=-=-=-=-=-=-=-=-=-=-=-= Cheers, Alexandre -- _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: Alexandre Bergel http://www.bergel.eu ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

Aug. 3, 2015

Re: [Pharo-users] Pillar hyperref and refs numbering

by Ferlicot D. Cyril

Le 03/08/2015 15:37, Sean P. DeNigris a Ã©crit : > jecisc wrote >> If you compile only 1 chapter in LaTeX then you will only have the >> numbering of the chapter. >> If you compile the whole book you will have the numbering of all chapters. > > This seems to come up quite a bit. Can we add a parameter to specify the > numbering when only compiling one chapter? > Hi, from my opinion this is useless because we export chapter by chapter only to avoid to spend 2min waiting LaTeX to finish his compilation when we work on a chapter. And when we work on a chapter we don't care if the numbering begin at the right number. When we are done with our chapter we can just launch the whole export and get the right numbering. If we work on a SquareBracketAssociates book, the CI will do the whole export by himself. > > > ----- > Cheers, > Sean > -- > View this message in context: http://forum.world.st/Pillar-hyperref-and-refs-numbering-tp4840747p4840773.… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >

Aug. 3, 2015

Re: [Pharo-users] Garage, Glorp, PostgreSQL and Cursors

by Esteban Lorenzano

> On 03 Aug 2015, at 15:35, Sean P. DeNigris <sean(a)clipperadams.com> wrote: > > vmusulainen wrote >> http://pharo.org/news/garage-database > > I'm also confused. What is the relationship between OpenDBX and Garage? IIRC > DBXTalk was the previous name of OpenDBX, right? Maybe an FAQ is in order as > the DB-related names seem to be multiplying ;) not really. DBXTalk is the suite that includes the OpenDBX driver (and others) it also includes Garage, as a common layer for different database drivers, one of them OpenDBX Esteban > > > > ----- > Cheers, > Sean > -- > View this message in context: http://forum.world.st/Garage-Glorp-PostgreSQL-and-Cursors-tp4840760p4840771… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >

Aug. 3, 2015

Re: [Pharo-users] Comparison for SequencableCollection

by jtuchel＠objektfabrik.de

Am 02.08.15 um 15:23 schrieb webwarrior: > > On 02.08.2015 15:44, jtuchel [via Smalltalk] wrote: > > I'd say it is questonable if SequenceableCollections should be > > comparable by default. > > > > is (a b c) equal or lower than (b a c) ? > > Doesn't this depend heavily on what is in the Collection and what the > > meaning of the Sequence of two Collections is? > > (a b c) = (b a c) if a = b > (a b c) < (b a c) if a < b > > The semantics are well defined. Are they? Why didn't the programmer use a Set then? She wanted to preserve the order of objects, right? So the order if objects matters to her, how does this weigh into your suggestion of comaprison? Don't get me wrong: your suggestion sounds logical and is correct. But so are others... > > Of course, it depends on what's in collection! That's the point - we > compare collections by their content. > If some elements are not comparable, we'll get DoesNotUnderstand - > expected behavior when comparing non-comparable objects. I am only talking about the sequence of objects. Ceteris paribus, what does the fact that one of the objects has a higher index in one collections mean in terms of being greater/equal/lower? > > It's the same story as with equality. so at first sight, you are correct: (a b c) = (b a c) if a = b But you aren't, because we are comparing Collections that only exist because the order of objects matter. For whatever reason that we can guess or not. > > > So I'd say there is not much use in putting comparisons into the base > > class library, because there is a ton of assumptions about the > > Collections in whatever implementation one can imagine. I would assume > > that this is the job of some business object that holds objects in a > > SequenceableCollection. Don't you think? > > There is only one assumption - that elements of the first collection are > comparable to the elements of the second collection. Only technically speaking. But if you wanted to only make sure you have the same objects in two collections, you'd probably use a Set or a Bag, no? And then, looking deeper: * What does it mean if element at position 3 in A is greater than B(3) and A(4) is lower than B(4) and all others are equal? * If collection A has 4 elements and B has 5. The first 4 are equal. Is B greater or lower than A? > > And I think that we shouldn't multiply entities beyond necessity by > creating a class when using simple datastructure would be sufficient. I am trying to make a point about exactly this not being true. The semantics of the sequence in a SequenceableCollection is completely out of scope of the Collection class. SequenceableCollections make sure your given ordering is preserved. But it has absolutely no idea why you chose that order and what it is good for. So while you are correct that we shouldn't build classes for no special reason other than that we can, the example at hand is not an argument to support it. It the sequence matters, then the semantics for the sequence needs to be modelled. There needs to be a class that models the knowledge about what the sequence is good for and - if necessary - can decide whether it is greater or lower than another instance of that very class. The SequenceableCollection is a data structure, not a business object. If there is semantics to a sequence, it is business knowledge. > > > The fact that other languages provide such an implementation doesn't > > mean much to me, to be honest. I choose a SequencableCollection in > order > > to keep objects in a certain order, nothing more, nothing less. > > That's why we have methods such as polynomialEval: and > asDigitsToPower:do: (and I'm not talking about extension methods) ? Maybe these methods have gotten where they are for the same reasons people use Associations and Dictionary all over the place. Laziness. Most of the times, this smells like technical debt. Joachim -- ----------------------------------------------------------------------- Objektfabrik Joachim Tuchel mailto:jtuchel@objektfabrik.de Fliederweg 1 http://www.objektfabrik.de D-71640 Ludwigsburg http://joachimtuchel.wordpress.com Telefon: +49 7141 56 10 86 0 Fax: +49 7141 56 10 86 1

Aug. 3, 2015

Re: [Pharo-users] Pillar hyperref and refs numbering

by Sean P. DeNigris

jecisc wrote > If you compile only 1 chapter in LaTeX then you will only have the > numbering of the chapter. > If you compile the whole book you will have the numbering of all chapters. This seems to come up quite a bit. Can we add a parameter to specify the numbering when only compiling one chapter? ----- Cheers, Sean -- View this message in context: http://forum.world.st/Pillar-hyperref-and-refs-numbering-tp4840747p4840773.… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Aug. 3, 2015

Re: [Pharo-users] Garage, Glorp, PostgreSQL and Cursors

by Sean P. DeNigris

vmusulainen wrote > http://pharo.org/news/garage-database I'm also confused. What is the relationship between OpenDBX and Garage? IIRC DBXTalk was the previous name of OpenDBX, right? Maybe an FAQ is in order as the DB-related names seem to be multiplying ;) ----- Cheers, Sean -- View this message in context: http://forum.world.st/Garage-Glorp-PostgreSQL-and-Cursors-tp4840760p4840771… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Aug. 3, 2015

Re: [Pharo-users] Garage, Glorp, PostgreSQL and Cursors

by Norbert Hartl

> Am 03.08.2015 um 15:11 schrieb Ð®ÑÐ¸Ð¹ ÐÐ¸ÑÐ¾Ð½ÐµÐ½ÐºÐ¾ <assargaddon(a)gmail.com>: > > I'm little bit shy, but what is Garage? http://pharo.org/news/garage-database <http://pharo.org/news/garage-database> Norbert > > 2015-08-03 15:33 GMT+03:00 Tommaso Dal Sasso <tommaso.dalsasso(a)gmail.com <mailto:tommaso.dalsasso@gmail.com>>: > Hello, > > I was trying the version of Glorp ported to Garage, and I must say it > runs smoothly, nice job! > > I am reading large amount of data from a Postgres db, and I was curious > about the use of cursors. > I remember that the old version of Glorp for Pharo did not support > cursors in Postgresql, has this changed in Garage? > > I tried to run some tests, using a query like: > > (Query readManyOf: MyClass) > collectionType: GlorpCursoredStream; > yourself. > > but with a large number of rows (~300k), the whole image crashes. > > Is this still not supported, or am I doing something wrong? > > Thanks, > Tommaso > >

Aug. 3, 2015

Re: [Pharo-users] Garage, Glorp, PostgreSQL and Cursors

by Alexandre Bergel

> I'm little bit shy, but what is Garage? Good question! Alexandre > > 2015-08-03 15:33 GMT+03:00 Tommaso Dal Sasso <tommaso.dalsasso(a)gmail.com <mailto:tommaso.dalsasso@gmail.com>>: > Hello, > > I was trying the version of Glorp ported to Garage, and I must say it > runs smoothly, nice job! > > I am reading large amount of data from a Postgres db, and I was curious > about the use of cursors. > I remember that the old version of Glorp for Pharo did not support > cursors in Postgresql, has this changed in Garage? > > I tried to run some tests, using a query like: > > (Query readManyOf: MyClass) > collectionType: GlorpCursoredStream; > yourself. > > but with a large number of rows (~300k), the whole image crashes. > > Is this still not supported, or am I doing something wrong? > > Thanks, > Tommaso > >

Aug. 3, 2015

Re: [Pharo-users] Garage, Glorp, PostgreSQL and Cursors

by Ð®ÑÐ¸Ð¹ ÐÐ¸ÑÐ¾Ð½ÐµÐ½ÐºÐ¾

I'm little bit shy, but what is Garage? 2015-08-03 15:33 GMT+03:00 Tommaso Dal Sasso <tommaso.dalsasso(a)gmail.com>: > Hello, > > I was trying the version of Glorp ported to Garage, and I must say it > runs smoothly, nice job! > > I am reading large amount of data from a Postgres db, and I was curious > about the use of cursors. > I remember that the old version of Glorp for Pharo did not support > cursors in Postgresql, has this changed in Garage? > > I tried to run some tests, using a query like: > > (Query readManyOf: MyClass) > collectionType: GlorpCursoredStream; > yourself. > > but with a large number of rows (~300k), the whole image crashes. > > Is this still not supported, or am I doing something wrong? > > Thanks, > Tommaso > >

Aug. 3, 2015