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SQL/mysql - Select distinct/UNIQUE but return all columns?
...ery:
SELECT * from table GROUP BY field1;
It will show all your results based on a single instance of field1.
For example, if you have a table with name, address and city. A single person has multiple addresses recorded, but you just want a single address for the person, you can query as follows...
Python Dictionary Comprehension
...
The main purpose of a list comprehension is to create a new list based on another one without changing or destroying the original list.
Instead of writing
l = []
for n in range(1, 11):
l.append(n)
or
l = [n for n in range(1, 11)]
you should write only
l = r...
Creating a blocking Queue in .NET?
...ty
/// </summary>
public ProducerConsumerQueue()
: base(new ConcurrentQueue<T>())
{
}
/// <summary>
/// Initializes a new instance of the ProducerConsumerQueue, Use Add and TryAdd for Enqueue and TryEnqueue and Take and TryTake for Dequeue and TryDequ...
How to change the timeout on a .NET WebClient object
...ed override WebRequest GetWebRequest(Uri uri)
{
WebRequest w = base.GetWebRequest(uri);
w.Timeout = 20 * 60 * 1000;
return w;
}
}
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What does “#pragma comment” mean?
... for help, clarification, or responding to other answers.Making statements based on opinion; back them up with references or personal experience.To learn more, see our tips on writing great answers.
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Preserving order with LINQ
...g to some rules.
GroupBy - The IGrouping objects are yielded in an order based on the order of the elements in source that produced the first key of each IGrouping. Elements in a grouping are yielded in the order they appear in source.
GroupJoin - GroupJoin preserves the order of the elements of ...
Attach parameter to button.addTarget action in Swift
...n addTarget:.One alternative is set the tag property of button and do work based on the tag.
button.tag = 5
button.addTarget(self, action: "buttonClicked:",
forControlEvents: UIControlEvents.TouchUpInside)
Or for Swift 2.2 and greater:
button.tag = 5
button.addTarget(self,action:#selector(b...
Changes in import statement python3
...script/package.
Consider the following tree for example:
mypkg
├── base.py
└── derived.py
Now, your derived.py requires something from base.py. In Python 2, you could do it like this (in derived.py):
from base import BaseThing
Python 3 no longer supports that since it's not explic...
URL-parameters and logic in Django class-based views (TemplateView)
It is unclear to me how it is best to access URL-parameters in class-based-views in Django 1.5.
5 Answers
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SQL SELECT WHERE field contains words
...need to look into full text search, and this is very specific for each database type.
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