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MongoDB Many-to-Many Association
... user document:
{name:"Joe"
,roles:["Admin","User","Engineer"]
}
To get all the Engineers, use:
db.things.find( { roles : "Engineer" } );
If you want to maintain the roles in separate documents then you can include the document's _id in the roles array instead of the name:
{name:"Joe"
,roles:...
Is there a way to pass optional parameters to a function?
Is there a way in Python to pass optional parameters to a function while calling it and in the function definition have some code based on "only if the optional parameter is passed"
...
Python matplotlib multiple bars
How to plot multiple bars in matplotlib, when I tried to call the bar function multiple times, they overlap and as seen the below figure the highest value red can be seen only.
How can I plot the multiple bars with dates on the x-axes?
...
Queries vs. Filters
...erefore faster than queries. Have a look here too. Let's say a query is usually something that the users type and pretty much unpredictable, while filters help users narrowing down the search results , for example using facets.
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Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
Split a string by a delimiter in python
...
@EndenDragon The for loop will automatically apply x.strip() and return a list of matches without whitespace on either side. The devil is in the details.
– Sébastien Vercammen
Jun 29 '16 at 13:59
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Is it possible to cache POST methods in HTTP?
...
The corresponding RFC 2616 in section 9.5 (POST) allows the caching of the response to a POST message, if you use the appropriate headers.
Responses to this method are not cacheable, unless the response
includes appropriate Cache-Control or Expires header fields. Howe...
Avoid browser popup blockers
...m javascript that is not invoked by direct user action. That is, you can call window.open in response to a button click without getting hit by the popup blocker, but if you put the same code in a timer event it will be blocked. Depth of call chain is also a factor - some older browsers only look a...
What does O(log n) mean exactly?
...g that the size of the input affects the growth of the algorithm proportionally...and the same goes for, for example, quadratic time O(n2) etc..even algorithms, such as permutation generators, with O(n!) times, that grow by factorials.
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Using async-await on .net 4
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Microsoft released the Async Targeting Pack (Microsoft.Bcl.Async) through Nuget as a replacement for the AsyncCTP.
You can read more about it here: http://blogs.msdn.com/b/bclteam/archive/2013/04/17/microsoft-bcl-async-is-now-st...