Wikipedia:Reference desk/Archives/Computing/2013 February 1

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February 1

MS Access - lookups

I have two lookup fields in Access, SuperType and SubType. There are 3 SuperTypes (Sup1, Sup2 and Sup3) and a record can have any number of them (0 - 3). Then there are multiple SubTypes and again, a record can have any number of them but some subtypes only apply when certain supertypes apply, for example, a record can't have the subtype "sub1" unless it also has the Supertype Sup1. Is there a way to enforce this restriction in Access 2010? Thanks, 86.45.222.91 (talk) 15:25, 1 February 2013 (UTC)

Not at the database level, I'm fairly sure. You can set up an interface that won't let you pick invalid fields, but that level of logical operation enforcement is not something the Access database can do. There may, in later version of Access, be event triggered before the table itself updates (independent of any form action) but I'm not sure. If there is you may be able to do a some kind of table-level enforcement by playing with the BeforeUpdate event of tables, but whether that makes sense or not (or is even necessary) depends on your particular implementation (and whether it is even possible). I would just make sure the Forms don't let you do anything that shouldn't be allowed and not worry about anything lower level than that, personally. --Mr.98 (talk) 01:30, 2 February 2013 (UTC)

I'm so disappointed in firefox and chrome

I am so disappointed in firefox and chrome for not being able to keep my state until *I* close the windows and tabs that I have open in private viewing mode.

Is it so hard to understand the difference between a crash, when it should apologize and reopen what just crashed, and me choosing to close a tab or window?

I don't like keeping any history whatsoever. But if I research something for hours, and assemble it like papers on my desk, is it so hard for firefox or chrome to understand that what I have open is important to me, and should not just disappear? Why can't they understand the fundamental difference between my closing something, and a crash?

I'm deeply disappointed in both projects. 178.48.114.143 (talk) 17:35, 1 February 2013 (UTC)

Agreed. The usual problem is they arrogantly think "We will never have a crash, so we don't need to worry about what to do if a crash occurs". Note that this isn't limited to browsers. It can also be annoying when a word processor or game dies after hours of work. If they were more reasonable, they would keep a running backup of everything you do, and allow you to pick up where you left off. Of course, this incurs overhead, so you might not always want to do so, but you should at least have the option. If they don't provide this choice, then the only way to avoid a serious loss of data is to "save often". I had this problem here in Wikipedia a while back, and resorted to copying my responses to the text clipboard before I picked submit, in case they were lost. StuRat (talk) 17:52, 1 February 2013 (UTC)

It shouldn't be hard. There should be a mode like "Private mode" called "Private, except if Firefox crashes reopen to same state." 178.48.114.143 (talk)

If the browsers ever wrote your state information to disk, it would be potentially accessible to forensic analysis even if you later "cleared" it. If that's what you're worried about, but you still want crash recovery, you will have to move your profile to a RAM disk (on Windows try ImDisk) or an encrypted volume (on Windows try TrueCrypt). If you don't care about that and just want a clean history, you can set it to clear automatically in Firefox and you can do it manually in Chrome (Ctrl+Shift+Delete). -- BenRG (talk) 18:27, 1 February 2013 (UTC)

Private mode means "don't under any circumstances write session data to the disk". So by using private mode you're telling it to not store history; now you're complaining that it hasn't stored history. If you just want it to erase history on a normal exit, do this instead of private browsing. -- Finlay McWalterჷTalk 18:11, 1 February 2013 (UTC)

To explain a bit of what I think the OP meant, it's not just going back to the original web pages that's important, but that those pages be in the same state you left them. For example, if I was editing a Wikipedia article, I want to go right back to the edit window, with my same text there as when it crashed. StuRat (talk) 18:15, 1 February 2013 (UTC)

Both Firefox and Chrome do keep a running record of what you're doing and do restore it after a crash, including partially-written Wikipedia edits. If you're not seeing that behavior, you just need to toggle some settings somewhere. But they won't in private browsing mode, because not keeping that kind of record is the whole point of private browsing mode. Although I suppose in principle they could run a server process whose only purpose was to save tab contents in RAM across crashes. -- BenRG (talk) 18:22, 1 February 2013 (UTC)

I would pay $50 for such a server process. Every time I use firefox for more than ten minutes, it's a race between me reading the material in my queue and whether firefox will crash before I do. During research projects this race gets a lot worse: I might open a lot of introductory level windows, definitions, tutorials, etc, and hope to get through it all before firefox crashes. it's elementary though and i dont need that stuff in my searches or history or anything else. i dont like history! I cannot believe that firefox cannot differentiate between a HISTORY (like the librarian saying, hey, here's everything you read before) and what is CURRENTLY OPEN ON YOUR DESKTOP. Why do I have to dread whether firefox will crash before I've read what I've opened? That stuff was hard to find- but I just intend to read it once, don't want bookmarks or history or anything else. 178.48.114.143 (talk) 19:08, 1 February 2013 (UTC)

Is OP using a shared computer? If not, other solutions may be more suited, like disk encryption. It all depends on how important data security is to him: if he simply doesn't like the idea of a history, I think there are less safe but more convenient privacy settings available. Ssscienccce (talk) 19:04, 1 February 2013 (UTC)

nah, I don't want disk encryption. I don't want to save history - i don't like having previous queries come up (such as low-level tutorials, when I mastered that stuff days ago), url's, different colored links, any of that stupid stuff. I don't need history and I don't like it. THat's why I use permanent private mode so that nothing is saved. At the same time, that doesn't mean the browser should just crash - and I *know* that it will. There isn't even a manual save button for saving all the windows and tabs that are currently open. Like I said, it's just a race between me and firefox/chrome to see if I can read what I've selected before they take that right away from me by crashing. Don't you agree that private mode shouldn't mean firefox will close your tabs and windows for you at random times? 178.48.114.143 (talk) 19:08, 1 February 2013 (UTC)

It seems you are unhappy because the software crashes. The symptom of that crash - which is the loss of your session - is a proxy. Whether you're in private- or not-private mode, the software should not crash. The best way to resolve this issue is to file a useful bug report about the crash and send it to the developer(s) of either application. For example, here's the Mozilla Bug Writing guidelines. If the software does not crash, you won't lose your data, whether in private-mode or otherwise.

It's worth stating for the record: if the software application's security model is "never write data to disk," then that privacy/security-model has a flaw. The application categorically has absolutely no control over what is written to disk. Such decisions are made by the operating system. If you must preserve the privacy and security of your data, you must use a secure operating system and you must encrypt all storage media. The application categorically can not guarantee that data remains "volatile." And the application can not guarantee that the operating system will never write contents of RAM to disk in an unencrypted fashion. Only the operating system, which must be secure, perfectly cooperate with all hardware, and remain free of any integrity-flaw, can guarantee that.

If the objective of "private mode" is not for security - but strictly for the user-interface benefits (such as the examples listed above), then the suggestions about using non-private-mode, but clearing history on clean exit, seems to be the correct way to do what you want. Nimur (talk) 20:06, 1 February 2013 (UTC)

Firefox can be configured to not show visited links in a different color, to not show pages from the history in the address bar dropdown, to use no space for the disk cache, and to erase everything on (successful) exit, all without private browsing turned on. -- BenRG (talk) 20:01, 1 February 2013 (UTC)

You're not here just to complain I hope? Because when you wanted a way to save all the tabs at once and I told you how to do it, you removed my answer and changed your complaint into "There isn't even a manual save button for saving all the windows and tabs that are currently open." Ssscienccce (talk) 20:56, 1 February 2013 (UTC)

I didn't notice your one line! I meant not to write so much and removed my own text. Let's reinstate it here (and sorry about that!):

Right-click tab choose "Bookmark all tabs". But you'll have to delete the folder when you're done. Ssscienccce (talk) 19:06, 1 February 2013 (UTC)

Unfortunately, when you have fifteen windows open, you have to do this 15 times - there is no option to do so for every window. I've done it from time to time: Paranoid Save 1, Paranoid Save 2, and so on, for fifteen folders. Later I know to delete them, since the only reason for this is in case of a crash. But does this seem like a reasonable thing to ask a user to do, when programmatically it would be approximately five lines of code to write: ForeachWindow(SaveALLintoTabs, "TEMP SAVE OF, " getdate, WindowNumber".") and similar to reopen them (For each /TEMP SAVE OF $requested/{openallinnewiwndow)), with an option to for each /TEMP SAVE OF $requested/{delete}. These were three pseudofunctions. It would take a programmer about 2 minutes to write it, five-fifteen to write it well, an hour to debug. Tops. I *need* this. 178.48.114.143 (talk) 23:08, 1 February 2013 (UTC)

As I said above, you can configure Firefox to disable visited-link coloring and url-bar history suggestions while still supporting session restore, which appears to be what you asked for. Is there something wrong with this solution? -- BenRG (talk) 23:43, 1 February 2013 (UTC)

What about cookies, etc etc etc. THere are a million things other than the url bar turning a different color. Now, if there really were a way to have Private Mode in EVERY sense except session restore it would be a different story. But I just don't think it's set up that way. There are always offline caches and whatnot slowing down firefox, unless you manually delete history or surf in private mode. (this is my understanding...correct me if I'm wrong!)178.48.114.143 (talk) 00:43, 2 February 2013 (UTC)

Recovering status after a crash involves continuously keeping a backup of your current status on the hard-drive.

If you're browsing in "Private Mode" it would be a security flaw to write your status to the hard-drive. (A clever enough investigator might be able to reconstruct part of your browser history, even after firefox wipes this temporary storage.)

I guess what you need is a "Somewhat Private Mode", good enough to fool snoopy relatives, but not guaranteed to defeat the FBI. I'm not aware of a browser that'll do that. (But like BenRG suggests above, you may be able to get close by individually turning off certain features.) APL (talk) 00:28, 2 February 2013 (UTC)

To be honest, I don't really agree with you. Imagine there is an "Untitled" notepad in another window showing all the current tabs. It's not being saved anywhere. When you manually close the last window, the text is thereby also down to empty again. As you open more lines, it fills up. But if firefox crashes you are left with an untitled notepad to decide what to do with. This doesn't mean it's being saved anywhere! It's just there, running, the same as Firefox as a moment ago, and as it still shoudl be... then you could decide to discard that notepad, or reopen those pages :) 178.48.114.143 (talk) 00:45, 2 February 2013 (UTC)

Perhaps you're hinting at a client-server model, which would allow the user-interface to crash, while preserving your session's run-time state in a daemon process. In fact, this is how recent Firefox works; various features are isolated from the user-session and the user-interface. The trouble is, once again, that if the top-level daemon process also crashes, then the state is lost. Nimur (talk) 02:56, 2 February 2013 (UTC)

This is true, but when the user-interface crashes (by itself), does it give you any way to recover if you're in Private Mode? I don't think it does. Perhaps it needs a popup that says "Firefox is crashing. Do you want to save your state even though that violates Private Mode? [yes] [no]" APL (talk) 20:42, 2 February 2013 (UTC)

LOL, I would *STILL* click "no" (to that phrasing), as I *still* don't want to save it! Instead it should say, "Private Mode Warning: Firefox is still running! Firefox began to crash, but is still running - all your windows and tabs are open. If you do nothing Firefox will stay open with the same windows and tabs. Or you can click below to quit Firefox immediately, and discard these tabs and windows forever. [Quit Firefox]". That's the proper way to do it. Firefox should quit whenever it closes without a crash. "Crashing" is not "quit"ing! It should be considered still-running... 178.48.114.143 (talk) 01:16, 3 February 2013 (UTC)

This is how it should look: (mockup only). You may inline it here if you know how! http://i.imgur.com/ZSHxG86.jpg <---- should look and function just like that :). 178.48.114.143 (talk) 01:54, 3 February 2013 (UTC)

@OP: Have you tried the Firefox add-on named: "Session Manager" found at:
https://addons.mozilla.org/en-US/firefox/addon/session-manager/?src=search
Maybe it will solve your problem…
--Seren-dipper (talk) 01:03, 4 February 2013 (UTC)

Ensuring English version Windows 7 or 8 laptop in Italy

I wish to buy a small new laptop for traveling such as an Acer, but it is essential the Windows operating system be in the English language.

I could buy a Windows 7 from the United Kingdom and pay high delivery charges, but I would rather buy locally in Italy or Switzerland.

1) What should I look for in the specification to guarantee the operating system is in English?

Windows 8 editions says all "editions have the ability to use language packs, enabling multiple user interface languages" sourced to [1]. Is this 100% reliable? Any gotcha's for non English Windows? I have been burnt before by a Microsoft hotfix for .NET under Italian Vista expecting an English OS. The claim is "have the ability to use" - what precisely must the user do to enable other languages?

2) Second, those that use Windows 8, is it really possible to set the desktop to the classic task bar look, i.e. completely avoiding the new touch interface?

My budget is under 450 Euros, and I'd be grateful for links to main Italian websites that might sell such. I already looked at http://www.e-key.it/ . -84user (talk) 18:13, 1 February 2013 (UTC)

I numbered your Q's. StuRat (talk) 18:19, 1 February 2013 (UTC)

1) I think you'll be safe on it having support for English, although the defaults might well be set to Italian, which could be annoying. If buying from a brick-and-mortar store, have them set in to English first, so you can verify it, before you buy it.

2) Yes, see http://classicshell.sf.net/. StuRat (talk) 18:20, 1 February 2013 (UTC)

1: Thanks, but I am still looking for something more concrete, prefereably from a user that has bought an Italian laptop and successfully set it to English. Looking at http://msdn.microsoft.com/en-gb/goglobal/ee461121 for Windows 7, I see that only "Full" "Complete language packs" provide the level of localisation I need - for example command line utilties must all report in English exactly the same way that a "native" English laptop would - it's that that borked my .NET install. Also, I cannot have, say, a Windows hotfix only available in English failing because the "base language" was in Italian. I am still looking for some Microsoft paper that talks about languages in much more depth in Windows 8.

2: Thanks, the Classic Shell is exactly what I would be looking for. -84user (talk) 18:47, 1 February 2013 (UTC)

Just thought I'd share my experience of being an aged windows user who moved to win8 a few months back - I was a bit unhappy with the new interface to start with as it is hard to adjust and I don't like change much, I only use a mouse and keyboard and sort of didn't see the point of why they changed. Now I'm really used to it, and when I try Win7 again it feels like stepping into the past. If I could choose now between Win7 and Win8 interfaces - I'd take Win8 interface. ---- _nonsense ferret 20:16, 1 February 2013 (UTC)

Do you have a touch screen ? Windows 8 seems to be set up for one, and I don't see the point in the huge changes, unless you actually have a touch screen. StuRat (talk) 23:25, 1 February 2013 (UTC)

Thanks for the feedback. Could you say which version of Windows 8 you have and whether it is indeed possible to add another language via the control panel without upgrading to Pro? And once added, do the error messages appear in that language? Do the "DOS" commands report in that language? -84user (talk) 21:07, 1 February 2013 (UTC)

I'm using pro, but from what I've read - the language packs are common functionality for all versions of Win8 - that represents a change compared with Win7 I believe which saw it as a premium feature. I decided to do a little fun experiment so I loaded the German language pack and used my computer - and I can confirm it seems to be pretty comprehensive change to the user interface. I was glad I could read enough to be able to change it back to english, but it was a close thing! You asked specifically about errors so I created a small wpf .net windows app with a button which triggered an application exception. I can confirm with the german language pack installed, the errors that I then created by running the app were in german, and on checking the windows eventvwr to look at the logs of all the system errors - the language of these was also fully in german. Of course there might be gotchas and its well worth continuing to google the issues rather than just relying on my say-so - but based on my experience I would be probably chance buying a pc in italy with win8 and changing the language pack to english and expect it to work as normal. I note that some language packs require a base language, but I don't think italian, german etc do. Of course different applications that you use will have their own arrangements regarding localisation, and particularly for Microsoft office - this will require a separate language pack which I haven't tested. Hope this is a little bit helpful. ---- _nonsense ferret 22:13, 1 February 2013 (UTC)

And you may find this link particularly interesting [2] ---- _nonsense ferret 22:41, 1 February 2013 (UTC)

You could try going into a local store, in which a salesman would probably be willing to prove to you a computer OS can use English as you prefer in order to potentially achieve a sale. Frequently you can get good deals in local shops, too, as at a certain point it is often imperative they make room for newer things. ¦ Reisio (talk) 21:20, 1 February 2013 (UTC)

WhatsApp tricks

Hi I got few questions about WhatsApp:
1)sometimes some group members leaves the group, and still sending messages.They aren't in the group but they still do.
How do they do it?
2)sometimes a group member shares a photo, which its preview (the tiny picture in the chat screen) is different from the photo which are shown, when I enlarge it. How does he do it? Exx8 (talk) —Preceding undated comment added 19:34, 1 February 2013 (UTC)