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How to include “zero” / “0” results in COUNT aggregate?
...e function count() will not count NULL values and thus you'll get a zero.
If you want to learn more about outer joins, here is a nice tutorial: http://sqlzoo.net/wiki/Using_Null
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Get line number while using grep
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that would be command line switch -v. If you run 'grep --help' it will display all options
– Miro A.
Jul 9 '10 at 16:05
56
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Get type of all variables
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Get worked perfectly. Do you know if there is any performance penalty if get() is used to find the type of several large data frames which may be present in the variable list returned by objects()?
– user1625066
Oct 2 '1...
How to get process ID of background process?
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... which hoses you if foo happens to be multiple piped commands (eg. tail -f somefile.txt | grep sometext). In such cases, you will get the PID of the grep command from $! rather than the tail command if that's what you were looking for. You wi...
Is it considered acceptable to not call Dispose() on a TPL Task object?
...posed to spinning or potentially
executing the task it's waiting on).
If all you're doing is using
continuations, that event handle will
never be allocated
...
it's likely better to rely on finalization to take care of things.
Update (Oct 2012)
Stephen Toub has posted a blog titled Do...
How to sort a list of strings?
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Basic answer:
mylist = ["b", "C", "A"]
mylist.sort()
This modifies your original list (i.e. sorts in-place). To get a sorted copy of the list, without changing the original, use the sorted() function:
for x in sorted(mylist):
print x
However, the examples above are a bit naive, ...
Removing multiple files from a Git repo that have already been deleted from disk
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@beanland, you need only provide the path to the specific file you want to modify if you don't want it to get them all. e.g. git add -u [path]
– Paul Prewett
Apr 10 '12 at 21:35
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Generic htaccess redirect www to non-www
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If it does not work, you are probably missing the RewriteEngine On precursor to make it work.
– hendry
May 25 '10 at 9:02
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Disable a group of tests in rspec?
...o I have to decide what to use again later), and is just as easily removed if the decision is made or blocker is removed.
This works the same for groups and individual examples.
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Android multiple email attachments using Intent
... be "text/plain" and not "plain/text": emailIntent.setType("text/plain");. If you use "plain/text" Android will force to use GMail as a sender, but if you use "text/plain" it will provide application chooser dialog with Gmail, Facebook, Bluetooth etc. If you would like to propose only mail programs ...