Wikipedia:Reference desk/Archives/Computing/2008 May 15

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May 15

Help- SQL

I am trying to get Microsoft Access (2000 version) to list all names in a table called "CUSTOMER", and then group those by LastName, FirstName ... but when I try:

SELECT *
FROM CUSTOMER
GROUP BY LastName, FirstName;

It says "Cannot group on fields selected with '*'"

When I try to list all of the fields in the database in the SELECT statement:
SELECT Phone, FirstName, LastName, Email
FROM CUSTOMER
GROUP BY LastName, FirstName;

It says "You tried to execute a query that does not include the specified instruction 'Phone' as part of an aggregate function."
-76.29.116.172 (talk) 02:08, 15 May 2008 (UTC)

The error is the same in both cases. When using a "GROUP BY" expression, you must include all of the columns rmentioned in the "SELECT" part. Using your examples, the second query should be:

SELECT Phone, FirstName, LastName, Email
FROM CUSTOMER
GROUP BY LastName, FirstName, Email, Phone

You could swap Email and Phone if you'd like. - SigmaEpsilon → ΣΕ 02:16, 15 May 2008 (UTC)

It's not clear to me what you're trying to achieve with GROUP BY in these examples. Do you mean you want to sort by LastName and FirstName? In that case the syntax SELECT * FROM CUSTOMER ORDER BY LastName, FirstName; should work. AndrewWTaylor (talk) 07:56, 16 May 2008 (UTC)

Indeed. Just to add further clarification - GROUP BY is always used in conjunction with an aggregation function such as SUM, AVG or COUNT. The GROUP BY clause determines the level at which the aggregation function is applied - without it, the function is applied across all rows retrieved, and the query result is a single row. If there is a GROUP BY clause then it must contain all of the non-aggregated columns from the SELECT clause - otherwise, you are selecting a column that does not appear in or affect the query result in anyway, so SQL assumes you have made a mistake.

There is more information on using GROUP BY here - but, as AndrewWTaylor says above, you should be using ORDER BY instead if you don't actually want any aggregation. Gandalf61 (talk) 09:35, 16 May 2008 (UTC)

VCS with Visual Studio 2008 Express

I asked a similar question a few weeks ago but got no answer. Let's try again...

Can I use a version control system (preferably a free one such as CVS) with Visual Studio 2008 Express? I've found some conflicting advice, with Microsoft suggesting it is possible but then it didn't explicitly mention the different editions of Visual Studio, whilst the information from Perforce suggested that their product didn't work with the 2005 Express Edition.

If it is possible, how is a non-Microsoft product integrated with the Visual Studio IDE? And can it all be on one PC (ie. database, server, and client all on the same disk on the same machine)?

Astronaut (talk) 03:12, 15 May 2008 (UTC)

free MySQL hosting

Is there any free MySQL hosting out there? (for testing purposes and to learn how to use it). GoingOnTracks (talk) 08:54, 15 May 2008 (UTC)

Just install MySQL on your own computer. --antilived^{T | C | G} 09:09, 15 May 2008 (UTC)

I wanted to test a web application. GoingOnTracks (talk) 09:25, 15 May 2008 (UTC)

Then install Apache too. If you use Windows, I suggest XAMPP - it's a bundle of Apache+PHP+MySQL+stuff. --grawity 11:57, 15 May 2008 (UTC)

Try www.ulmb.com or www.phpnet.us. Phpnet is simpler but not as reliable, and ulmb is better but had used safe mode to the max. Adam (Manors) 12:08, 15 May 2008 (UTC)

Free flash flex server

is there any free flex server out there? GoingOnTracks (talk) 10:49, 15 May 2008 (UTC)

Ebay

Some eBay users have a bot program. I know this because those users somehow make a bid for an item they want about half a second after I make it. Could someone tell me where I can download this program? Interactive Fiction Expert/Talk to me 11:12, 15 May 2008 (UTC)

This is referred to as "sniping". I use Auction Sentry, but there are several other sniping applications available. --— Gadget850 (Ed)talk 11:17, 15 May 2008 (UTC)

Ebay also has their own automatic bid system, where it will overbid anyone else, up to a bidding limit you define. Unfortunately, if two people are bidding on the same item using this system, it assures that one will pay the highest amount possible, given both their limits. StuRat (talk) 16:51, 15 May 2008 (UTC)

which is probably good for the seller but not for the buyer? Kushal (talk) 18:21, 15 May 2008 (UTC)

Wouldn't this be the same level reached if they had both bided conventionally? -- Q Chris (talk) 07:27, 16 May 2008 (UTC)

Not necessarily, because when bidding conventionally it takes time for people to notice that others have overbid them and then respond. Thus, the bid period can end before this maximum is reached. StuRat (talk) 14:59, 18 May 2008 (UTC)

IFE, You're not seeing bots. This is just how eBay works. The number you type into the bidding box is maximum bid you're willing to pay. eBay will automaticly figure out the least you can pay and still be the top bidder, and post your bid like that (to save you money, if possible.), however it remembers your maximum bid and will re-bid for you if someone places a bid that is less than your maximum. They call this Proxy Bidding.

There are such things as eBay bots, but I've never even heard of one that works like you describe, it would be counter-productive. Typically a bot to handle eBay bidding will not place any bids until about ten seconds before the auction closes and then place a winning bid. That way it avoids running up the bidding by letting the human bidders believe they are going to win. The proxy bidding that you noticed is actually designed to mitigate the effect and annoyance of the bots. (If my maximum bid is high enough, it doesn't matter if a bot comes in at the last second. I've got it covered.) APL (talk) 20:04, 16 May 2008 (UTC)

Archive.org

If a website shuts down, does Archive.org keep the already archived files, or are they deleted? Atkinson's GM (talk) 12:23, 15 May 2008 (UTC)

The archives are maintained. If you are looking to archive a reference in an aricle, check out LinkChecker. It checks all the article links- if it finds a dead link, it can automatically search Archive.org and update the link. --— Gadget850 (Ed)talk 12:34, 15 May 2008 (UTC)

It keeps them. If User:Mr Beans Backside is blocked, does User:Atkinson's gluteus maximus get deleted too? -- Hoary (talk) 12:37, 15 May 2008 (UTC)

Looks like yes to both. Didn't even look at the user name. --— Gadget850 (Ed)talk 12:46, 15 May 2008 (UTC)

Visual Basic 2005 question re: images

I am trying to work on a project in Visual Basic 2005 in which I'm going to want to apply (programmatically) filter to a grayscale image where it will convert it to a black-and-white image in a way that I can adjust the threshold depending on the image. What's the best approach to take, here? I feel like ImageMagick might be a bit overkill for this one need -- is there any native way that VB can deal with image manipulation of this sort? It strikes me that going through pixel-by-pixel on my own is going to be very slow so I'd like to avoid that at all costs. --98.217.8.46 (talk) 16:19, 15 May 2008 (UTC)

Nevermind, I found this code that helped out a lot. Basically I do end up running through it pixel-by-pixel but using the GDI+ framework that works pretty quickly. --98.217.8.46 (talk) 00:37, 16 May 2008 (UTC)

Using Mediawiki

I've recently taken interest in the concept of personal wikis. I looked around but couldn't find anything which suited my needs, things like Wikipad or web-based wiki applications. I know Mediawiki is suited for large wiki-farms and not for personal note-taking, but I've grown used to Wikipedia's interface and as such, I'd like to use it to sort my notes and thoughts. The thing is, I do not wish to make any of it available on the internet. Is it possible for me to create an offline database and run Mediawiki on my machine alone? -- 83.132.220.63 (talk) 18:24, 15 May 2008 (UTC)

Well, you can run Mediawiki offline, but that's probably overkill if you are just going to do note taking. But yeah; install Apache, install MySQL, install PHP, install MediaWiki, run it off the localhost. --98.217.8.46 (talk) 18:53, 15 May 2008 (UTC)

There is a spectacular little application called TiddlyWiki which is a personal wiki that's just a single HTML file. Download the file, open it in a webbrowser, and BAM!, you have a wiki. And a pretty frickin' cool wiki. No need for a database or server or anything. It's FANTASTIC for note-taking. --Oskar 22:45, 15 May 2008 (UTC)

Photoshopping

Resolved

 – Trolling...... Dendodge .. Talk^Help 19:46, 15 May 2008 (UTC)

Could someone who is good at photoshopping tell me if this image has been faked http://img213.imageshack.us/img213/717/brightonsy4.jpg —Preceding unsigned comment added by 222.132.241.179 (talk) 19:33, 15 May 2008 (UTC)

Well, what do you think? Yes...... Dendodge .. Talk^Help 19:46, 15 May 2008 (UTC)

No, it's a real photo. If you look really closely, you can see the thin wires holding up the cardboard cutouts. <g, d & r> —Ilmari Karonen (talk) 20:27, 15 May 2008 (UTC)

And the birds?...... Dendodge .. Talk^Help 20:32, 15 May 2008 (UTC)

Printed on transparent plastic and hung from wires. Duh. —Ilmari Karonen (talk) 20:40, 15 May 2008 (UTC)

But they're all identical, with a white splodge in the same relative position (like a bad photoshop). I can't see any wires either but...... Dendodge .. Talk^Help 21:23, 15 May 2008 (UTC)

This looks shopped. I can tell from the pixels, and from having seen many shops in my day. Ziggy Sawdust 23:03, 16 May 2008 (UTC)

You call that Photoshopping? It's been painted, not photoshopped! Photoshopping won't give you this distinctive style.--antilived^{T | C | G} 00:30, 17 May 2008 (UTC)

Are you asking if the actual application Adobe Photoshop has been used to create this image? It's possible, but doubtful. A skilled Photoshop user would have to turn of many of the default settings to get results this bad. It IS a digitally manipulated image, but it's impossible to tell if Photoshop was used to create it. --70.167.58.6 (talk) 16:23, 20 May 2008 (UTC)

Coppermine Gallery

Could someone kind please tell me what would be the best program to harvest all the images from this Coppermine Photo Gallery [1] Thanks. Lop lop 7 (talk) 20:50, 15 May 2008 (UTC)

HTTrack is pretty all-purpose useful as a spider. --98.217.8.46 (talk) 04:11, 16 May 2008 (UTC)

Wiki Nested Tables

I was wondering how to make the inner table on this larger table fill in the whole space.
Thanks in advance. -- Ishikawa Minoru (talk) 21:55, 15 May 2008 (UTC)

Perhaps the Help Desk would be better suited to answer that. Useight (talk) 06:56, 16 May 2008 (UTC)

Why on earth are you doing nested table in the first place? It's very bad web design practice. --antilived^{T | C | G} 07:31, 16 May 2008 (UTC)

Acer Aspire

What is the lastest Acer Aspire and what major retailer sells it? House1561 (talk) 23:09, 15 May 2008 (UTC)

Thanks to Acer Aspire, I reached [Acer notebook page] where AS 9920 has the highest product number. Here] is the specification grid, which you may want to look at. I am sorry I cannot give you more concrete answers at the moment. Kushal (talk) 13:11, 16 May 2008 (UTC)