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INNER JOIN vs LEFT JOIN performance in SQL Server
...point out that there is basically no database documentation to support the idea that inner joins and outer joins performance differently. Outer joins are slightly more expensive than inner joins, because of the volume of the data and the size of the result set. However, the underlying algorithms (...
Possibility of duplicate Mongo ObjectId's being generated in two different collections?
...ce you don't control the ObjectId generation function, it's probably a bad idea to rely on it.
– slacy
Jan 13 '11 at 7:02
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Convert a Git folder to a submodule retrospectively?
... useful as a standalone component (a library, perhaps). If you've had that idea from early on, then there's a fair chance that most of that code is in its own folder.
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How can I add reflection to a C++ application?
...ion TS in Visual Studio here:
https://developercommunity.visualstudio.com/idea/826632/implement-the-c-reflection-ts.html
Talk on the TS by the author David Sankel:
http://cppnow.org/history/2019/talks/
https://www.youtube.com/watch?v=VMuML6vLSus&feature=youtu.be
Edit 17 March 2020
Progress...
C++ - passing references to std::shared_ptr or boost::shared_ptr
... work with really, really know what you are all doing.
First, you have no idea how the interface to your class might evolve and you want to prevent other programmers from doing bad things. Passing a shared_ptr by reference isn't something a programmer should expect to see, because it isn't idiomati...
Why do I need 'b' to encode a string with Base64?
...omes a string. A string is a sequence of Unicode characters. base64 has no idea what to do with Unicode data, it's not 8-bit. It's not really any bits, in fact. :-)
In your second example:
>>> encoded = base64.b64encode('data to be encoded')
All the characters fit neatly into the ASCII ...
What do Clustered and Non clustered index actually mean?
...uld be ordered so that one can simply do address arithmetic to search. The idea of the cluster is to cater the table to the performance of a particular index. To be clear, the records of the table will be reordered to match the order that the index is originally in.
– FLGMwt
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Android Left to Right slide animation
...time, no matter what, it does the left to right animation. Anyone have any ideas???
– Ryan C
Feb 28 '15 at 23:55
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What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and be
...ust a single matrix, with the R matrix embedded in the upper triangle. No idea where the rest of the matrix comes from, and no Q matrix can be accessed.
Armadillo
Advantages:
1. Wide range of decompositions and other functions (including QR).
2. Reasonably fast (uses expression templates), but aga...
ASP.NET Identity's default Password Hasher - How does it work and is it secure?
...calling SHA1 1000 times means that the
attacker also needs to do this. The idea being that unless they have
time on a supercomputer they won’t have enough resource to brute
force the password from the hash. It would massively slow down the time to generate a hash table for a given salt.
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