* Re: databases written in ada [not found] ` <3D547FFD.3030808@cogeco.ca> @ 2002-08-10 5:13 ` Christopher Browne 2002-08-10 9:13 ` Florian Weimer 2002-08-11 17:34 ` Heikki Tuuri 1 sibling, 1 reply; 7+ messages in thread From: Christopher Browne @ 2002-08-10 5:13 UTC (permalink / raw) The world rejoiced as "Warren W. Gay VE3WWG" <ve3wwg@cogeco.ca> wrote: > tony wrote: > > but in which when something is stored then it is automatically > > stored to disk as well as being available in memory > > This comment, as worded, is difficult to understand precisely. APQ > as well as any other Ada binding to an SQL database gives you the > opportunity to insert rows, perform updates, perform deletes, or > perform SELECT queries and retrieve results. There is also the GNADE > project, which gives you the ability to do "embedded SQL" in Ada > terms. The comment is fairly readily understood, as it is commonly known in OS literature by the term "orthogonal persistence." The idea is that you have a set of datatypes which essentially "store themselves." You don't have to do a "select" or "insert" or "update" in order to get/put values. Instead, by virtue of simply having a declaration like: value1, value2 : INTEGER; Those values are directly tied to the database. If you have the code: value1 := 25; value2 := 17; value1 := value1 + value2; This would, behind the scenes, intersperse the assignments with queries that might resemble: insert into int_table (key, value) values ('value1', 25); insert into int_table (key, value) values ('value2', 17); update int_table set value = 32 where key = 'value1'; It is quite common to set up database-backed classes in Java and C++ that create this sort of tie between objects and SQL databases. The cool part is that if the program were shut down, you could [by some Really Complex magic I'll not imagine too hard about] see the program start back up, and continue where it left off, with the various variables holding their database-backed values. Presumably you could create an Ada class that would allow doing something sort of like this. Presumably you'd not want _all_ variables database-backed, as performance would Suck Spectacularly. But it's a pretty normal exercise using JDBC to design classes to let you define some "database-backed variables." It probably ought to be left as an exercise for the reader :-) -- (reverse (concatenate 'string "moc.enworbbc@" "sirhc")) http://www3.sympatico.ca/cbbrowne/linux.html "So, does this mean goodbye to the "Bluescreen of Death" and hello to the "Bluescreen of Holy Vengeance?"" -- Observed on Slashdot after hearing Al Qaeda terrorists may have hacked on Windows XP... ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: databases written in ada 2002-08-10 5:13 ` databases written in ada Christopher Browne @ 2002-08-10 9:13 ` Florian Weimer 2002-08-10 15:22 ` Christopher Browne 0 siblings, 1 reply; 7+ messages in thread From: Florian Weimer @ 2002-08-10 9:13 UTC (permalink / raw) Christopher Browne <cbbrowne@acm.org> writes: > The comment is fairly readily understood, as it is commonly known in > OS literature by the term "orthogonal persistence." > > The idea is that you have a set of datatypes which essentially "store > themselves." And how is this supposed to work if there are multiple users of the same database? ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: databases written in ada 2002-08-10 9:13 ` Florian Weimer @ 2002-08-10 15:22 ` Christopher Browne 2002-08-11 13:20 ` Florian Weimer 0 siblings, 1 reply; 7+ messages in thread From: Christopher Browne @ 2002-08-10 15:22 UTC (permalink / raw) Quoth Florian Weimer <fw@deneb.enyo.de>: > Christopher Browne <cbbrowne@acm.org> writes: >> The comment is fairly readily understood, as it is commonly known in >> OS literature by the term "orthogonal persistence." >> >> The idea is that you have a set of datatypes which essentially "store >> themselves." > > And how is this supposed to work if there are multiple users of the > same database? I suppose that means that the datatypes have to be able to have some sort of identity so that you can distinguish between instances that may be associated with a particular user and those that need to have 'global' scope and would be shared across users. I didn't say it was going to be _easy_ :-). -- (reverse (concatenate 'string "gro.mca@" "enworbbc")) http://www.ntlug.org/~cbbrowne/sap.html "What I find most amusing about com and .NET is that they are trying to solve a problem I only had when programming using MS tools." -- Max M <maxm@mxm.dk> (on comp.lang.python) ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: databases written in ada 2002-08-10 15:22 ` Christopher Browne @ 2002-08-11 13:20 ` Florian Weimer 0 siblings, 0 replies; 7+ messages in thread From: Florian Weimer @ 2002-08-11 13:20 UTC (permalink / raw) Christopher Browne <cbbrowne@acm.org> writes: >> And how is this supposed to work if there are multiple users of the >> same database? > > I suppose that means that the datatypes have to be able to have some > sort of identity so that you can distinguish between instances that > may be associated with a particular user and those that need to have > 'global' scope and would be shared across users. This won't solve the fundamental problem: even if you automatically introduce transactions, the underlying database will sometimes have to roll back transactions if they are not serializable. As a result, the transaction has to be started from scratch. I don't see how you can do this implicitly (at least in a language which is not purely functional). ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: databases written in ada [not found] ` <3D547FFD.3030808@cogeco.ca> 2002-08-10 5:13 ` databases written in ada Christopher Browne @ 2002-08-11 17:34 ` Heikki Tuuri 2002-08-15 22:02 ` Poutanen Olavi 1 sibling, 1 reply; 7+ messages in thread From: Heikki Tuuri @ 2002-08-11 17:34 UTC (permalink / raw) Hi! "Warren W. Gay VE3WWG" <ve3wwg@cogeco.ca> wrote in message news:3D547FFD.3030808@cogeco.ca... > tony wrote: > > does anyone know of any databases written in ada in which ada types can > > be stored. I'm looking for something which is very basic, ... > > I am personally not aware of _any_ database that is written in Ada. > > PostgreSQL is a good Open Sourced database, if "open source" is one of your > requirements. Another is MySQL, although it lacks transactions, which is > something I consider essential functionality (I understand that they > now (finally) understand that they do need it, and now working in that > direction to provide it). MySQL nowadays has full support of transactions through the InnoDB and BDB backends. ... > Warren. Best regards, Heikki Tuuri Innobase Oy --- InnoDB - transactions, row level locking, and foreign key support for MySQL See http://www.innodb.com, download MySQL-Max from http://www.mysql.com ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: databases written in ada 2002-08-11 17:34 ` Heikki Tuuri @ 2002-08-15 22:02 ` Poutanen Olavi 0 siblings, 0 replies; 7+ messages in thread From: Poutanen Olavi @ 2002-08-15 22:02 UTC (permalink / raw) :> > does anyone know of any databases written in ada in which ada types can :> > be stored. I'm looking for something which is very basic, ... :> :> I am personally not aware of _any_ database that is written in Ada. A very looong time ago I was involved in the Nokia MPS 10 project. That was a proprietary hw architecture machine that had Ada as its sole programming language (or more precicely, Ada/MPS, which was quite near to Ada 83). I was project manager in a project, where we implemented a relational database management system in Ada, DMS/MPS 10. That work has been reported in the Ada-Europe conference (see the proceedings book) that was held in Paris (in 1984?). Olavi Poutanen Testwell Oy www.testwell.fi Testing tools for [Ada 83], C, C++ and Java ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: databases written in ada [not found] <3D53CE34.45F25F4@btinternet.com> [not found] ` <3D547FFD.3030808@cogeco.ca> @ 2002-08-10 7:20 ` Caffeine Junky 1 sibling, 0 replies; 7+ messages in thread From: Caffeine Junky @ 2002-08-10 7:20 UTC (permalink / raw) On Fri, 09 Aug 2002 10:14:53 -0400, tony wrote: > does anyone know of any databases written in ada in which ada types can > be stored. I'm looking for something which is very basic, but in which > when something is stored then it is automatically stored to disk as well > as being available in memory Check out the Eaglespeed and FIRM databases over at http://www.lockheedmartin.com/syracuse/eaglespeed/ They're written in Ada(as far as I know), but they are a little pricey. St4pL3 ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2002-08-15 22:02 UTC | newest] Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- [not found] <3D53CE34.45F25F4@btinternet.com> [not found] ` <3D547FFD.3030808@cogeco.ca> 2002-08-10 5:13 ` databases written in ada Christopher Browne 2002-08-10 9:13 ` Florian Weimer 2002-08-10 15:22 ` Christopher Browne 2002-08-11 13:20 ` Florian Weimer 2002-08-11 17:34 ` Heikki Tuuri 2002-08-15 22:02 ` Poutanen Olavi 2002-08-10 7:20 ` Caffeine Junky
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