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PostgreSQL DISTINCT ON with different ORDER BY
I want to run this query:
6 Answers
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How to get error message when ifstream open fails
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Every system call that fails update the errno value.
Thus, you can have more information about what happens when a ifstream open fails by using something like :
cerr << "Error: " << strerror(errno);
However, since every s...
Differences between numpy.random and random.random in Python
...of much higher quality than is available from random.random alone. You usually don't need this, though.
– SingleNegationElimination
Aug 11 '11 at 18:36
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How to install a specific JDK on Mac OS X?
I want to install a specific JDK (the latest for example). For this, I went to the JDK download homepage: http://java.sun.com/javase/downloads/index.jsp .
I looked for a Mac version, but I'm a bit surprised to only see downloadable versions for Linux, Windows and Solaris ...
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How can I determine if a variable is 'undefined' or 'null'?
...enceError and break execution if variable is not defined or referred to at all in the code, using typeof is safer.
– Mani Gandham
Jun 15 '14 at 9:49
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change text of button and disable button in iOS
...antage of the fact that they are passed in as an argument to the IBAction calls:
- (IBAction) triggerActionWithSender: (id) sender;
This can be bound to the button and you’ll get the button in the sender argument when the action is triggered. If that’s not enough (because you need to access t...
What do I need to read to understand how git works? [closed]
...Magic explained how to get started
Git The Basics [pdf] explained - graphically, and in detail - what happens when I add, remove, merge, etc.
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An error occurred while installing pg (0.17.1), and Bundler cannot continue
I just installed Rails 4.0.2 and when creating a new app, in the bundle stage I get:
16 Answers
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How to use a class from one C# project with another C# project
...that you wish to access directly must have a sufficient access level: typically this means they must be made public.
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Create a dictionary with list comprehension
...(key)) for key in keys)
In simple cases you don't need a comprehension at all...
But if you already have iterable(s) of keys and/or values, just call the dict built-in directly:
1) consumed from any iterable yielding pairs of keys/vals
dict(pairs)
2) "zip'ped" from two separate iterables of keys/v...