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The SQL OVER() clause - when and why is it useful?
...t
GROUP BY [Partition]
) agg ON orig.[Partition] = agg.[Partition]
Now look how you can do the same with a windowed aggregate:
SELECT
[Partition],
Value,
Value * 100.0 / SUM(Value) OVER (PARTITION BY [Partition]) AS ValuePercent
FROM OriginalRowset orig
Much easier and cleaner, isn'...
How to convert OutputStream to InputStream?
...a OutputStream and second one, which accepts only InputStream . Do you know how to convert OutputStream to InputStream (not vice versa, I mean really this way) that I will be able to connect these two parts?
...
Generate random numbers uniformly over an entire range
...rface. While theoretically also being an external dependency, Boost has by now a status of "quasi-standard" library, and its Random module could be regarded as the classical choice for good-quality random number generation. It features two advantages with respect to the C++11 solution:
it is more ...
Why is __init__() always called after __new__()?
...it__ takes self as parameter. Until you create instance there is no self.
Now, I gather, that you're trying to implement singleton pattern in Python. There are a few ways to do that.
Also, as of Python 2.6, you can use class decorators.
def singleton(cls):
instances = {}
def getinstance(...
Most efficient way of making an if-elif-elif-else statement when the else is done the most?
...dictionary :
options = {'this': doThis,'that' :doThat, 'there':doThere}
Now use just:
options.get(something, doThisMostOfTheTime)()
If something is not found in the options dict then dict.get will return the default value doThisMostOfTheTime
Some timing comparisons:
Script:
from random imp...
Should you ever use protected member variables?
...
The general feeling nowadays is that they cause undue coupling between derived classes and their bases.
They have no particular advantage over protected methods/properties (once upon a time they might have a slight performance advantage), and t...
Python __call__ special method practical example
I know that __call__ method in a class is triggered when the instance of a class is called. However, I have no idea when I can use this special method, because one can simply create a new method and perform the same operation done in __call__ method and instead of calling the instance, you can c...
Spring Test & Security: How to mock authentication?
...t(
basicActiveUser, managerActiveUser
));
}
}
Now we have our users ready, so imagine we want to test the access control to this controller function:
@RestController
@RequestMapping("/foo")
public class FooController {
@Secured("ROLE_MANAGER")
@GetMapping("/salu...
how to log in to mysql and query the database from linux terminal
...nect to mysql database on linux machine from windows machine using sqlyog.
Now I want to execute queries on linux machine only using linux terminal
...
Importing from builtin library when module with same name exists
...
The accepted solution contains a now-deprecated approach.
The importlib documentation here gives a good example of the more appropriate way to load a module directly from a file path for python >= 3.5:
import importlib.util
import sys
# For illustrativ...