[Angela Woods]

Don't forget transactions, ensuring the consistency of data, locking of rows etc. Writing a database is non trivial. Given time I am fairly sure I could write one that exceeded the performace of MySql, for my specific task. I don't have those months to put into it though.

[Alex [AK]]

Don't forget transactions, atomicity, ..., locking of rows.

What, what and what?

I'm serious, I need to know what those three mean in order to know how difficult it would be to program.

[kyle pinchen]

What, what and what?

I'm serious, I need to know what those three mean in order to know how difficult it would be to program.

From Wikipedia:

A database transaction comprises a unit of work performed within a database management system (or similar system) against a database, and treated in a coherent and reliable way independent of other transactions. Transactions in a database environment have two main purposes:
* To provide reliable units of work that allow correct recovery from failures and keep a database consistent even in cases of system failure, when execution stops (completely or partially) and many operations upon a database remain uncompleted, with unclear status.
* To provide isolation between programs accessing a database concurrently. Without isolation the program's outcomes are possibly erroneous.

Atomicity requires that database modifications must follow an "all or nothing" rule. Each transaction is said to be atomic. If one part of the transaction fails, the entire transaction fails and the database state is left unchanged. It is critical that the database management system maintain the atomic nature of transactions in spite of any application, DBMS (Database Management System), operating system or hardware failure.

See: http://en.wikipedia.org/wiki/ACID

Locking of rows: You can't have two separate processes, both with write access to the same row. Same sort of thing as the issues with multi threading.



As said. Non trivial.

[Rodney C]

From Wikipedia:

A database transaction comprises a unit of work performed within a database management system (or similar system) against a database, and treated in a coherent and reliable way independent of other transactions. Transactions in a database environment have two main purposes:
* To provide reliable units of work that allow correct recovery from failures and keep a database consistent even in cases of system failure, when execution stops (completely or partially) and many operations upon a database remain uncompleted, with unclear status.
* To provide isolation between programs accessing a database concurrently. Without isolation the program's outcomes are possibly erroneous.


Atomicity requires that database modifications must follow an "all or nothing" rule. Each transaction is said to be atomic. If one part of the transaction fails, the entire transaction fails and the database state is left unchanged. It is critical that the database management system maintain the atomic nature of transactions in spite of any application, DBMS (Database Management System), operating system or hardware failure.

Locking of rows: You can't have two separate processes, both with write access to the same row. Same sort of thing as the issues with multi threading.

Okay, so... what exactly is the problem supposed to be? I must admit that I don't even know what this "database" is supposed to do. Is it supposed to work across a network (Internet), so the main program is a server with the database and other people use client programs to manipulate the database?

[Jodie Bardgett]

Okay, so... what exactly is the problem supposed to be? I must admit that I don't even know what this "database" is supposed to do. Is it supposed to work across a network (Internet), so the main program is a server with the database and other people use client programs to manipulate the database?

It will be a large database of mods, their download locations, and the current state of the parse process (there can be multiple concurrent parsers with a shared state). Clients can interact with this database. (Search it).

I already have something that does the same with about 40k mods. It just failed big time as I made a load of trivial mistakes. This is basically me writing the new version and trying to avoid the trivial mistakes I made (And no doubt making a whole load of other mistakes).

[Del Arte]

It will be a large database of mods, their download locations, and the current state of the parse process (there can be multiple concurrent parsers with a shared state). Clients can interact with this database. (Search it).

Is it supposed to be able to provide services through web browsers (like on a web page)? Because if it is then that's a wholly different kind of headache...

[DAVId MArtInez]

Is it supposed to be able to provide services through web browsers (like on a web page)? Because if it is then that's a wholly different kind of headache...

Yeah...

[Nicole Coucopoulos]

Anyways. With Veeno's suggestion to look at another way, I am using an index indicating a mods version at that location. Insertions are a lot slower, but on the plus side lookups are faster and the amount of code has been reduced. So overall probably a plus

But why oh why doesn't PHP have a stable sort <_<

[Soph]

But why oh why doesn't PHP have a stable sort <_<

Do it yourself? :hehe:


Yeah I see a pattern here as well...

[Enie van Bied]

Do it yourself? :hehe:


Yeah I see a pattern here as well...

Well, in this case it is probably the right answer. . I can't claim that Insertion Sort is hard to implement.

[YO MAma]

I'm so bored. I just got into GUI programming and I want to make new programs all the time now. Any ideas?

[Genevieve]

You could figure out what the issue was with that program we were working on. Otherwise I am working on a gradebook I could use help with if you wanted. Then again all my new projects use WPF and if I recall right you are running Linux and can't run them. Otherwise what you can do is just find small repetetive tasks you perform often and make a program to automate it.

WPF has been driving me crazy. I am having a tough time wrapping my head around data binding and I used a DataGrid for one of my programs and I can't figure out how to get the value of the third column. Getting a bit frustrated with it.

[Luis Reyma]

You could figure out what the issue was with that program we were working on. Otherwise I am working on a gradebook I could use help with if you wanted. Then again all my new projects use WPF and if I recall right you are running Linux and can't run them. Otherwise what you can do is just find small repetetive tasks you perform often and make a program to automate it.

WPF has been driving me crazy. I am having a tough time wrapping my head around data binding and I used a DataGrid for one of my programs and I can't figure out how to get the value of the third column. Getting a bit frustrated with it.

Well actually, I have been working on the mod installer. I attempted to get it to remove the presets keys from the registry. But I don't know if it works. And I finished the Output class.

[Haley Cooper]

Take Adderall.

[Tanya]

Well actually, I have been working on the mod installer. I attempted to get it to remove the presets keys from the registry. But I don't know if it works. And I finished the Output class.

Removing should be rather simple. I am going to grab Subversion here real fast and perhaps give the program a look later tonight. I have class all day and tomorrow I will be buried in books for most of the day. I think this weekend I might have more of a chance to do some work on it though.

Does anyone know how to access a specific cell in a datagrid using WPF? I have my data bound to the various columns but I need to pull the data from columns two and three for every row (variable amount) for processing. I can't really seem to find anything on Google which is driving me nuts. I think I may end up just using a ListView but I need to ability to modify some of the data before processing.

[MR.BIGG]

Do you guys think C++ is worth learning nowadays? I know a bit about object-oriented programming and have been learning C# for quite awhile. But will C++ still be "needed" or in-demand in the future with all these frameworks and runtimes (.NET) that automate programs?

So basically, should I continue learning C#, or start learning C++ and all its lower level features?

[SEXY QUEEN]

Do you guys think C++ is worth learning nowadays? I know a bit about object-oriented programming and have been learning C# for quite awhile. But will C++ still be "needed" or in-demand in the future with all these frameworks and runtimes (.NET) that automate programs?

So basically, should I continue learning C#, or start learning C++ and all its lower level features?

Continue c# and when you need some c++ functions just import them into c#

[Emma louise Wendelk]

Do you guys think C++ is worth learning nowadays? I know a bit about object-oriented programming and have been learning C# for quite awhile. But will C++ still be "needed" or in-demand in the future with all these frameworks and runtimes (.NET) that automate programs?

So basically, should I continue learning C#, or start learning C++ and all its lower level features?

It depends what you are using it for. C++ will always be useful when high performance is necessary as the programmer has much better control over it than the likes of Java or C#.

[kelly thomson]

Do you guys think C++ is worth learning nowadays?

A silly question. Of course it is.

To be honest though, you should probably wait until http://en.wikipedia.org/wiki/C%2B%2B0x is finalised and made the new standard.

[Kay O'Hara]

Do you guys think C++ is worth learning nowadays? I know a bit about object-oriented programming and have been learning C# for quite awhile. But will C++ still be "needed" or in-demand in the future with all these frameworks and runtimes (.NET) that automate programs?

Even if you learn C++ and never use it, you will still probably find it useful.

For example, given the knowlege that strings are immuable in Java this would make any C++ or C programmer horrified (The C programmer would probably shoot you)

String s   = "Hello World ";String tmp = "";for (int i = 0; i < times; i++) {    tmp += s;}

Understanding how things work at a lower level is almost always useful.


Having said that. C++ isn't a great language from a design standpoint. I still hope D overtakes C++. Not that it will happen any time soon but I can hope.

To be honest though, you should probably wait until C++0x is finalised and made the new standard.

To be honest though, someone new to C++ isn't going to need much of C++0x and in any case, most compilers support the majority of the latest C++0x draft. :shrug:


Plus, if the compiler doesn't support it, you should just implement it yourself





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[teeny]

So I'll be learning C++ along with advancing C#. How similar are the two? Besides the name of course.

[Bereket Fekadu]

ugh, I'm having some trouble with a website I'm working on.

Basically I need to load specific content from another website into an iframe on my site. I've been messing around with jquery and ajax for an hour and I haven't made any progress. <_<

Any suggestions on how to do that?


to be more specific, I need to scraqe the contents of a

element from another html file and place them in an iframe.

[Phoenix Draven]

ugh, I'm having some trouble with a website I'm working on.

Basically I need to load specific content from another website into an iframe on my site. I've been messing around with jquery and ajax for an hour and I haven't made any progress. <_<

Any suggestions on how to do that?


to be more specific, I need to scraqe the contents of a

element from another html file and place them in an iframe.

So this site isn't part of yours? Just one from the internet?

[NAkeshIa BENNETT]

So this site isn't part of yours? Just one from the internet?

Yes.

and no I'm not stealing from the website. I checked.

[Eliza Potter]

to be more specific, I need to scraqe the contents of a

element from another html file and place them in an iframe.

Unfortunately you can't do this on the client side due to the http://en.wikipedia.org/wiki/Same_origin_policy. I would suggest making a simple passthrough proxy on your server side and going through it.