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RSpec: describe, context, feature, scenario?
...scenario : What is the difference(s) among the four and when do I use each one?
3 Answers
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Swapping column values in MySQL
...able schema at the end of the post. This method doesn't swap the values if one of them is NULL. Use method #3 that doesn't have this limitation.
UPDATE swap_test SET x=y, y=@temp WHERE (@temp:=x) IS NOT NULL;
This method was offered by Dipin in, yet again, the comments of http://beerpla.net/2009/02...
How does TransactionScope roll back transactions?
...Transaction Scope) and if so enlist with it. Caution if there are more the one connection to the same SQL server this will escalate to a Distribtued Transaction.
What happens since you're using a using block you are ensuring dispose will be called even if an exception occurs. So if dispose is call...
“On-line” (iterator) algorithms for estimating statistical median, mode, skewness, kurtosis?
...ate parameter (e.g. 0.001), and sgn() is the signum function which returns one of {-1, 0, 1}. (Use a constant eta if the data is non-stationary and you want to track changes over time; otherwise, for stationary sources you can use something like eta=1/n for the mean estimator, where n is the number ...
When should I use @classmethod and when def method(self)?
...n classes. The author seems to use them both very intentionally. The first one is one I myself use a lot:
3 Answers
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Why doesn't Java Map extend Collection?
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what are the keys? There's no really
satisfactory answer, and forcing one
leads to an unnatural interface.
Maps can be viewed as Collections (of
keys, values, or pairs), and this fact
is reflected in the three "Collection
view operations" on Maps (keySet,
entrySet, and values). W...
What's the difference between 'git merge' and 'git rebase'?
... Nice illustrations. However, I do not fully agree with the positive tone that rebase is handled. In both merge and rebase conflicts can occur that need manual resolution. And as always when programmers are involved there is a non-neglectable chance of errors aka bugs. If a merge error happens ...
Why can I access TypeScript private members when I shouldn't be able to?
...g Module Pattern, so the private members can remain private and the public ones can be accessible in JavaScript. This is a common pattern and would provide the same accessibility in TS and JS.
– John Papa
Dec 19 '12 at 1:42
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Mongodb Explain for Aggregation framework
...to fetch the initial data for a pipeline (e.g. usage of $match, $sort, $geonear at the beginning of a pipeline) as well as subsequent $lookup and $graphLookup stages. Once data has been fetched into the aggregation pipeline for processing (e.g. passing through stages like $project, $unwind, and $g...
Applying function with multiple arguments to create a new pandas column
...owing this answer I've been able to create a new column when I only need one column as an argument:
5 Answers
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