Wikipedia:Reference desk/Archives/Computing/2011 April 6

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April 6

please help

YouTube download

I want to download this movie from YouTube. Among the best qualities, there are two options available: MP4 360p and FLV 480p. Which will be better in quality? Are MP4 videos better in quality? Please help, i have a slow internet connection and it takes a lot of time to download videos in my computer. I want the better quality video. --Houlok (talk) 05:54, 6 April 2011 (UTC)

In general I'm not sure there's an easy way to determine whether the MP4 or the FLV will be better quality — what you'd want, ideally, is whichever one is the least transcoded. So if the MP4 is just a conversion to MP4 from FLV, you'd want the FLV; if the MP4 is the raw file from which the FLV was made, you'd want the MP4. Sorry that isn't super helpful. In theory the FLV would be higher resolution at 480p, but my experience is that often these numbers are quite misleading (just yesterday I downloaded one from YouTube which KeepVid.com had said was higher resolution than another format, but they were, once downloaded, identical in terms of their actual pixel ratios). The biggest argument towards downloading MP4 is that you probably already have video software to view it with. FLV usually requires plug-ins or extra codecs of some sort. --Mr.98 (talk) 18:28, 6 April 2011 (UTC)

I added a more useful (sub)title. StuRat (talk) 23:58, 6 April 2011 (UTC)

Disable interpretation of tipping on the pad as click

Hi,

how can I disable the behaviour of my laptop touchpad to inerpret the tipping on the pad as a click? I am using a Dell Inspiron with With Windows 7 Home Premium. Toshio Yamaguchi (talk) 12:19, 6 April 2011 (UTC)

This is known as 'Tap to click,' and you will find the option to disable in the Control Panel under 'Mouse'. Depending on your drivers, it may be in one of a number of tabs. Let us know if you have any trouble.--rocketrye12 ^{talk/contribs} 20:46, 6 April 2011 (UTC)

Problem with SQL outer joins

I ran into a rather complicated problem with SQL today at work. We are using the following kind of SQL query:

SELECT a.name, b.name, c.name, d.name FROM
tablea a, tableb b, tablec c, tabled d
WHERE b.aid(+) = a.id
AND c.bid(+) = b.id
AND d.id(+) = c.did

The idea is that this query must return rows even if no matching row is found from tableb, tablec or tabled, but if no matching rows are found from tablec or tabled, then b.name must be null even if there's actually a value there. I tried various ways of configuring the outer joins but couldn't find a way to do it the right way. Sorry for the nondescriptive names used in this example, but the actual code is under our company's copyright. Can anyone help me to achieve this kind of thing in SQL? JIP | Talk 18:44, 6 April 2011 (UTC)

Just to make sure we understand what you want, could you give us sample data and the desired result ? StuRat (talk) 23:57, 6 April 2011 (UTC)

Suppose tablea contains the following data:

name	id
Tarja Halonen	1
Carl XVI Gustaf	2
Angela Merkel	3
Palpatine	4

tableb contains the following data:

name	id	aid
Finland	10	1
Sweden	20	2
Germany	30	3

tablec contains the following data:

bid	did
10	100
20	200

tabled contains the following data:

name	id
Helsinki	100
Stockholm	200

I want to be able to return every row in tablea, even though Palpatine can't be linked to any of the other tables. However, I don't want Germany to show up along with Angela Merkel, because it can't be linked to tablec or tabled, instead it should show up as null. JIP | Talk 17:44, 7 April 2011 (UTC)

(That doesn't quite match your SELECT statement, since there's no c.name column.) Do you want to see something like this ?

Tarja Halonen    Finland   Helsinki
Carl XVI Gustaf  Sweden    Stockholm
Angela Merkel
Palpatine

If so, perhaps your query might look like this:

 (SELECT a.name, b.name, d.name 
    FROM tablea a, tableb b, tablec c, tabled d
   WHERE b.aid = a.id
     AND c.bid = b.id
     AND d.id  = c.did)
UNION
 (SELECT a.name, " ", " " 
    FROM tablea a, tableb b
   WHERE b.aid != a.id)

StuRat (talk) 06:19, 8 April 2011 (UTC)

OK, thanks for your reply. Sorry for the mismatch between the examples, but I'm glad you understood it anyway. Your example output above is exactly what I would want. However I was hoping to avoid a union of multiple select queries, as in the real-world case, the tables have many more columns and at least tablea is joined to more tables, which are irrelevant to this question. The actual query is quite long and isn't even written as static text but instead built dynamically because parts of it can change. Having a union would mean having to repeat all this. I've managed to work around the problem by having the code that reads the result ignore values from tableb that can't be linked to tablec or tabled. JIP | Talk 18:09, 8 April 2011 (UTC)

You're welcome. Other than a UNION, I can't think of a way to do what you want. Note that the second SELECT is much short (and quicker), since we no longer need to worry about the joins to tables C and D. Hopefully something similar will happen in your case. The UNION seems well-suited for the type of program you described. In this example, all it would have to do is change the equals to a not equals in the first WHERE clause, omit the remaining where clauses, and omit the columns and tables which are no longer needed. Now, if it's not just the column data which is dynamic in the query, but also the logic (like adding new tables for some queries), then that is getting complex. Perhaps you could automate some of the most common complex queries by writing code to handle them. If you can give me examples of the range of queries, perhaps I can come up with some sample code, using embedded SQL. In this example, we could have one possible option be "Select all leaders, and, if both a nation and capital are available, list both". StuRat (talk) 19:27, 8 April 2011 (UTC)

igoogle side tabs

Hi. As of this morning, my fixes to remove the igoogle side tabs on firefox don't work (the tabs appear on the left side of my igoogle page, with idiotic things like "gadget shares" and "friends"--things I have no interest in, and waste my screen real-estate). Bad google. My greasemonkey script, having given good service for a year or so, now doesn't get rid of them, and the firefox plug-in doesn't work either. I'm going to have to switch to netvibes or similar if I can't sort this out. Any genius out there with an idea how to remove those stupid side tabs? Robinh (talk) 20:56, 6 April 2011 (UTC)

When you say "my fixes," are you referring to said greasemonkey script? Greasemonkey scripts are of course at the mercy of any code changes google may make to that page, in addition to any browser compatibility issues that may be introduced in major or minor releases. I did find this discussion here which you could try, though I haven't tested it myself. But...at the end of the day, as we say in web development 'if you didn't build it, don't bank on it!' --rocketrye12 ^{talk/contribs} 21:01, 6 April 2011 (UTC)

Hello Rocketry12. Thanks for this. Yup, my fixes are (or, were)-: the greasemonkey script, and a firefox add-on. Neither seem to work now. Why are google being such jerks? Robinh (talk) 23:16, 6 April 2011 (UTC)

(OP). Well, I spoke too soon. There is a "Super iGoogle" greasemonkey script, which has a patch, as of last week, that seems to work for me. Thanks, everyone! I can use igoogle again! Robinh (talk) 23:31, 6 April 2011 (UTC)