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MySQL “Group By” and “Order By”
.... GROUP BY is case insensitive so LOWER() is unnecessary, and second, $userID appears to be a variable directly from PHP, your code may be sql injection vulnerable if $userID is user-supplied and not forced to be an integer.
– velcrow
Apr 23 '13 at 18:09
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Meaning of $? (dollar question mark) in shell scripts
...ho $? # echoes 0
false
echo $? # echoes 1
From the manual: (acessible by calling man bash in your shell)
$? Expands to the exit status of the most recently executed foreground pipeline.
By convention an exit status of 0 means success, and non-zero return status means failu...
How to check if a string is a valid hex color representation?
... By definition this is correct, but codes with a length of 3 are valid for browser interpretation, too. color: #f00; will be interpreted as red (#ff0000) aswell.
– Smamatti
Nov 6 '11 at 14:13
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log messages appearing twice with Python Logging
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You are calling configure_logging twice (maybe in the __init__ method of Boy) : getLogger will return the same object, but addHandler does not check if a similar handler has already been added to the logger.
Try tracing calls to th...
Qt events and signal/slots
...nveniently:
Since we reimplemented a virtual, our implementation automatically became encapsulated in our class. If Qt's designers had made keyPressEvent a signal, we would need to decide whether to inherit QPushButton or just externally connect to the signal. But that would be stupid, since in Qt...
Why use Abstract Base Classes in Python?
...lemented classes.
Long version
There is a contract between a class and its callers. The class promises to do certain things and have certain properties.
There are different levels to the contract.
At a very low level, the contract might include the name of a method or its number of parameters.
In a ...
iOS JavaScript bridge
... allowing complete communication between the two.
However, you can easily call from javascript custom-made URLs, like:
window.location = yourscheme://callfunction/parameter1/parameter2?parameter3=value
And intercept it from Objective-C with this:
- (BOOL)webView:(UIWebView*)webView shouldStartL...
Is it good style to explicitly return in Ruby?
...e, it's fine. Clearly if somewhere further down the code chain, something calling this is expecting a returned value, it's going to fail as it's not getting back what it expects.
The real question now is this: did anything really expect a returned value? Did this break something or not? Will it...
How is Perl's @INC constructed? (aka What are all the ways of affecting where Perl modules are searc
...It also should be used when the directory to be searched needs to be dynamically determined during runtime - e.g. from the script's command line parameters or script's path (see the FindBin module for very nice use case).
If the directories in @INC need to be manipulated according to some complicate...
Java int to String - Integer.toString(i) vs new Integer(i).toString()
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Integer.toString calls the static method in the class Integer. It does not need an instance of Integer.
If you call new Integer(i) you create an instance of type Integer, which is a full Java object encapsulating the value of your int. Then ...