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How important is the order of columns in indexes?
... Also keep in mind, suppose your Index is like the picture above, and your query filters on column1 and column2, but column2 is more unique and what you really want to filter on is actually column2, then its more beneficial to just have a index where column 2 is first. This may seem counte...
How to merge remote changes at GitHub?
... for details.
You can perform "git pull", resolve potential conflicts, and "git push" the result. A "git pull" will create a merge commit C between commits A and B.
Alternatively, you can rebase your change between X and B on top of A, with "git pull --rebase", and push the result back. The...
“On-line” (iterator) algorithms for estimating statistical median, mode, skewness, kurtosis?
Is there an algorithm to estimate the median, mode, skewness, and/or kurtosis of set of values, but that does NOT require storing all the values in memory at once?
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How to update Python?
... 2012. I can't find any consensus on whether I should completely uninstall and wipe this version before putting on the latest version.
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What are the effects of exceptions on performance in Java?
Question: Is exception handling in Java actually slow?
18 Answers
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How do cache lines work?
I understand that the processor brings data into the cache via cache lines, which - for instance, on my Atom processor - brings in about 64 bytes at a time, whatever the size of the actual data being read.
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Numpy `logical_or` for more than two arguments
...arrays? (The same question could be asked with regard to Numpy's logical_and and obtaining the intersection of more than two arrays.)
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What is Mocking?
...-memory structure for storing records. The object under test can then read and write records to the database stub to allow it to execute the test. This could test some behavior of the object not related to the database and the database stub would be included just to let the test run.
If you instead ...
DynamoDB vs MongoDB NoSQL [closed]
...ject, we plan to store from about 500k records per month in the first year and maybe more for the next years this is a vertical application so there's no need to use a database for this, that's the reason why I decided to choose a noSQL data storage.
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What are the differences between type() and isinstance()?
...of a base class, too), while checking for equality of type does not (it demands identity of types and rejects instances of subtypes, AKA subclasses).
Normally, in Python, you want your code to support inheritance, of course (since inheritance is so handy, it would be bad to stop code using yours fr...