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<p class=MsoNormal>As I’m a selfmade man, I never really studied
relational databases in detail. My intuition told me that the “relational”
part was not really suitable for the 3D data, 2D images, animation curves, state
machines, and other data I encountered in the videogame and animation business.
I could always get away with files, and for the applications I needed to deploy,
plugging in a couple of extra gigabytes of RAM and serializing the “object”
state to disk was more practical, cheaper and faster. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>However, a couple of years ago I started studying computer
science (I seem to do the theory after the practice, weird behavior ;-) at the
Open University, and one of the exams I did was about databases. Initially this
course convinced me that databases are actually very nice, but the course ended
with a topic on object oriented databases, which were designed to make storing
data like “3D models, graphs, networks, and complex datastructures”
more practical. Duh.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Since then, I did deploy a few commercial applications for
customers using databases, which worked fine for the typical “simple/flat”
database data. I hated embedding a dynamic untyped language like SQL, as much
as I hated embedding code in HTML or XML… IMHO it feels UGLY and unsafe. Regarding
the other popular data storage format – XML – I did use that a lot,
but it seems like going back to the stone ages, when hierarchical stores/databases
got invented (and ditched?)<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Now, initially after an introduction to Microsoft’s LINQ,
and recently having read a very brief overview of HAppS, it seems I’m not
the only one with those “feelings”. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Ouch, this introduction got way to long, sorry about that
;-)<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Finally some practical questions:<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:38.4pt;text-indent:-.25in;
mso-list:l2 level1 lfo3'><![if !supportLists]><span style='font-family:Symbol'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>regarding Haskell and <b>databases</b>, the page
<a href="http://haskell.org/haskellwiki/Libraries_and_tools/Database_interfaces">http://haskell.org/haskellwiki/Libraries_and_tools/Database_interfaces</a>
describes a few, but which are the ones that are <b>stable</b> and <b>practical</b>?
Any user experiences?<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:38.4pt;text-indent:-.25in;
mso-list:l2 level1 lfo3'><![if !supportLists]><span style='font-family:Symbol'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><b>HApps</b> is not listed in the page above,
because it does not use databases? Is HApps reliable or experimental, and does
it scale well? Any success stories?<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:38.4pt;text-indent:-.25in;
mso-list:l2 level1 lfo3'><![if !supportLists]><span style='font-family:Symbol'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>regarding Haskell and <b>serialization, </b>I
don’t think that implementing Read/Show is a good way for real
serialization, so what other options exist? I could find some libraries at <a
href="http://hackage.haskell.org/packages/archive/pkg-list.html#cat:Data">http://hackage.haskell.org/packages/archive/pkg-list.html#cat:Data</a>,
but again which are the most practical and stable? When programming in C++/MFC
and C#/.NET, I tended to develop my own serialization frameworks because I used
that for many things, like logging commands to disk, performing undo/redo, intra
and inter process cut/copy/paste, save/load, etc…<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:38.4pt;text-indent:-.25in;
mso-list:l2 level1 lfo3'><![if !supportLists]><span style='font-family:Symbol'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>Regarding serialization, I’m kinda curious
how ADTs and even GADTs are stored and retrieved in a relational database? I
guess it could be done using BLOBs and serialization to ByteStrings, so bypassing
a lot of the database table structures?<o:p></o:p></p>
<p class=MsoListParagraph style='margin-left:38.4pt;text-indent:-.25in;
mso-list:l2 level1 lfo3'><![if !supportLists]><span style='font-family:Symbol'><span
style='mso-list:Ignore'>·<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]>If I would want to experiment with say HAppS, the
way I understand it, I first would first have to study “Scratch your
boilerplate” and Template Haskell, and maybe some other language features?
I’m still new to Haskell, and the road to understanding all language
elements and extensions is very long, so sequentially learning it would be
insane I guess. I have no practical experience with TH, but I spent a long time
trying to do “aspect oriented programming” in C# without success,
so TH looks uber to me…<o:p></o:p></p>
<p class=MsoNormal> <o:p></o:p></p>
<p class=MsoNormal>Thanks a lot and best wishes for 2008?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Peter<o:p></o:p></p>
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