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Unique fields that allow nulls in Django
...ar field should be unique, but allow nulls in it, meaning I want to allow more than one record if bar field is null , but if it is not null the values must be unique.
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How to convert Set to Array?
...e elements, but it does not expose any good way to get properties, except for generator [Set].values, which is called in an awkward way of mySet.values.next() .
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How to properly compare two Integers in Java?
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No, == between Integer, Long etc will check for reference equality - i.e.
Integer x = ...;
Integer y = ...;
System.out.println(x == y);
this will check whether x and y refer to the same object rather than equal objects.
So
Integer x = new Integer(10);
Integer y = ...
Is there a software-engineering methodology for functional programming? [closed]
Software Engineering as it is taught today is entirely focused on object-oriented programming and the 'natural' object-oriented view of the world. There is a detailed methodology that describes how to transform a domain model into a class model with several steps and a lot of (UML) artifacts like us...
Which is faster: multiple single INSERTs or one multiple-row INSERT?
...ta into MySQL. Should I chain INSERTs to make one huge multiple-row INSERT or are multiple separate INSERTs faster?
10 Answ...
Using SASS with ASP.NET [closed]
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For a better working experience in Visual Studio, you could install the last version of Web Essential which is starting to support Sass (SCSS syntax). Alternatively you could install Sassy Studio or Web Workbench.
Then to com...
How to import the class within the same directory or sub directory?
I have a directory that stores all the .py files.
13 Answers
13
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How to add minutes to my Date
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The issue for you is that you are using mm. You should use MM. MM is for month and mm is for minutes. Try with yyyy-MM-dd HH:mm
Other approach:
It can be as simple as this (other option is to use joda-time)
static final long ONE_MI...
What are forward declarations in C++?
At: http://www.learncpp.com/cpp-tutorial/19-header-files/
8 Answers
8
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