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How much size “Null” value takes in SQL Server
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If the field is fixed width storing NULL takes the same space as any other value - the width of the field.
If the field is variable width the NULL value takes up no space.
In addition to the space required to store a null value there is also an o...
Why do we need the “event” keyword while defining events?
...to private, so that only the containing class can invoke the event or override all the methods contained in it. The -= and += operators can still be invoked on an event from outside the class defining it (they get the access modifier you wrote next to the event).
You can also override the way -= and...
How do I edit the Visual Studio templates for new C# class/interface?
...m.Xml.
2005:
C:\Program Files (x86)\Microsoft Visual Studio 8\Common7\IDE\ItemTemplates\CSharp\1033\Class.zip
2008:
C:\Program Files (x86)\Microsoft Visual Studio 9.0\Common7\IDE\ItemTemplates\CSharp\Code\1033\Class.zip
2010:
C:\Program Files (x86)\Microsoft Visual Studio 10.0\Commo...
Twig for loop for arrays with keys
... var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled...
How to send only one UDP packet with netcat?
... might as well write
echo -n "hello" >/dev/udp/localhost/8000
and avoid all the idiosyncrasies and incompatibilities of netcat.
This also works sending to other hosts, ex:
echo -n "hello" >/dev/udp/remotehost/8000
These are not "real" devices on the file system, but bash "special" alias...
.rar, .zip files MIME Type
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multipart/x-zip is a valid mimetype for .zip as well ( PKZIP archive )
– Sam Vloeberghs
Mar 4 '13 at 13:52
13
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What is the _snowman param in Ruby on Rails 3 forms for?
...4), I see that when using the form_tag or form_for helpers there is a hidden field named _snowman with the value of ☃ ( Unicode \x9731) showing up.
...
How to upgrade Eclipse for Java EE Developers?
...the juno release repo. It was confusing that some of the updated features did not show as installed, even thought they were.
– Mark Mikofski
Jul 25 '13 at 6:28
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How to set child process' environment variable in Makefile
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As MadScientist pointed out, you can export individual variables with:
export MY_VAR = foo # Available for all targets
Or export variables for a specific target (target-specific variables):
my-target: export MY_VAR_1 = foo
my-target: export MY_VAR_2 = bar
my-target: ex...
Count occurrences of a char in plain text file
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How about this:
fgrep -o f <file> | wc -l
Note: Besides much easier to remember/duplicate and customize, this is about three times (sorry, edit! botched the first test) faster than Vereb's answer.
sha...