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MySQL: Set user variable from result of query
Is it possible to set an user variable based on the result of a query in MySQL?
4 Answers
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How to use Bash to create a folder if it doesn't already exist?
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First, in bash "[" is just a command, which expects string "]" as a last argument, so the whitespace before the closing bracket (as well as between "!" and "-d" which need to be two separate arguments too) is important:
if [ ! -d /home/mlzboy/b2c2...
Setting a timeout for socket operations
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Use the Socket() constructor, and connect(SocketAddress endpoint, int timeout) method instead.
In your case it would look something like:
Socket socket = new Socket();
socket.connect(new InetSocketAddress(ipAddress, port), ...
List of encodings that Node.js supports
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The list of encodings that node supports natively is rather short:
ascii
base64
hex
ucs2/ucs-2/utf16le/utf-16le
utf8/utf-8
binary/latin1 (ISO8859-1, latin1 only in node 6.4.0+)
If you are using an older version than 6.4.0, or don't want to deal with non-...
Is effective C++ still effective?
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This what Scott Meyers himself had to say about it on his own blog
Which may lead you to wonder whether the information and advice in
this pre-C++0x edition of Effective C++ remains relevant. I'm pleased
to report that it does. Surprisingly so, in fact. Having s...
How do I force detach Screen from another SSH session?
I had Screen running inside an SSH session. Terminal froze. After restarting Terminal, that Screen session still thinks it's attached. Maybe it is. Perhaps I don't really know what that means.
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Add a space (“ ”) after an element using :after
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Explanation
It's worth noting that your code does insert a space
h2::after {
content: " ";
}
However, it's immediately removed.
From Anonymous inline boxes,
White space content that would subsequently be collapsed away
according to the 'white-space' ...
Python super() raises TypeError
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The reason is that super() only operates on new-style classes, which in the 2.x series means extending from object:
>>> class X(object):
def a(self):
print 'a'
>>> class Y(X):
def a(self):
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How to negate the whole regex?
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Use negative lookaround: (?!pattern)
Positive lookarounds can be used to assert that a pattern matches. Negative lookarounds is the opposite: it's used to assert that a pattern DOES NOT match. Some flavor supports assertions...
Purging file from Git repo failed, unable to create new backup
I tried to remove a file from my remote repo by running:
4 Answers
4
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