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How to create a unique index on a NULL column?
...rver 2005. I want to constrain the values in a column to be unique, while allowing NULLS.
4 Answers
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Exit a Script On Error
... If you like the ABS, you'll love the BashGuide, BashFAQ and BashPitfalls.
– Paused until further notice.
Dec 8 '10 at 4:45
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How do I make a fully statically linked .exe with Visual Studio Express 2005?
...g any other libraries you may need to tell the linker to ignore the dynamically linked CRT explicitly.
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E731 do not assign a lambda expression, use a def
...rst form means that the name of the resulting
function object is specifically 'f' instead of the generic '<lambda>'.
This is more useful for tracebacks and string representations in
general. The use of the assignment statement eliminates the sole
benefit a lambda expression can offer o...
Replace a value if null or undefined in JavaScript
... boolean value but the first value that can be converted to true.
Additionally use an array of objects instead of one single object:
var options = {
filters: [
{
name: 'firstName',
value: 'abc'
}
]
};
var filter = options.filters[0] || ''; // is {n...
How to post data to specific URL using WebClient in C#
...s the garbage collector will clean up unmanaged resources and the like by calling the destructor (e.g., WebClient inherits from Component, which contains ~Component() {Dispose(false);}). The problem is that the garbage collector may take an arbitrarily long time to do so, since it does not account ...
Are there any reasons to use private properties in C#?
...et
{
if (_password == null)
{
_password = CallExpensiveOperation();
}
return _password;
}
}
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How do you log server errors on django sites
...
Well, when DEBUG = False, Django will automatically mail a full traceback of any error to each person listed in the ADMINS setting, which gets you notifications pretty much for free. If you'd like more fine-grained control, you can write and add to your settings a middlew...
Why can't I define a default constructor for a struct in .NET?
...type a default constructor is created (by the compiler?) which initialized all members to zero (or null ).
10 Answers
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Rails 4: List of available datatypes
...
Here are all the Rails 4 (ActiveRecord migration) datatypes:
:binary
:boolean
:date
:datetime
:decimal
:float
:integer
:bigint
:primary_key
:references
:string
:text
:time
:timestamp
Source: http://api.rubyonrails.org/classes/Acti...