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How do I create a unique constraint that also allows nulls?
I want to have a unique constraint on a column which I am going to populate with GUIDs. However, my data contains null values for this columns. How do I create the constraint that allows multiple null values?
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recursion versus iteration
Is it correct to say that everywhere recursion is used a for loop could be used? And if recursion is usually slower what is the technical reason for ever using it over for loop iteration?
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Best practice? - Array/Dictionary as a Core Data Entity Attribute [closed]
I am new to Core Data. I have noticed that collection types are not available as attribute types and would like to know what the most efficient way is of storing array/dictionary type data as an attribute (e.g. the elements that make up an address like street, city, etc. does not require a separate ...
Representing null in JSON
...ut as always, it depends on what you're doing -- sometimes the "right" way to do it doesn't always work for your situation. Use your judgement and make an informed decision.
JSON1 {}
This returns an empty object. There is no data there, and it's only going to tell you that whatever key you're look...
Programmatically saving image to Django ImageField
Ok, I've tried about near everything and I cannot get this to work.
17 Answers
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Load a UIView from nib in Swift
Here is my Objective-C code which I'm using to load a nib for my customised UIView :
27 Answers
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How can you program if you're blind?
... for granted. Most programmers would spend hours looking at a computer monitor (especially during times when they are in the zone ), but I know there are blind programmers (such as T.V. Raman who currently works for Google).
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Compiling C++ on remote Linux machine - “clock skew detected” warning
I'm connected to my university's small Linux cluster via PuTTY and WinSCP, transferring files using the latter and compiling and running them with the former. My work so far has been performed in the university's labs, but today I have been doing some work at home that generated an interesting warn...
The new syntax “= default” in C++11
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A defaulted default constructor is specifically defined as being the same as a user-defined default constructor with no initialization list and an empty compound statement.
§12.1/6 [class.ctor] A default constructor that is defaulted and not defined a...
RegEx match open tags except XHTML self-contained tags
I need to match all of these opening tags:
35 Answers
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