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Does the join order matter in SQL?
... FULL) OUTER joins, yes, the order matters - and (updated) things are much more complicated.
First, outer joins are not commutative, so a LEFT JOIN b is not the same as b LEFT JOIN a
Outer joins are not associative either, so in your examples which involve both (commutativity and associativity) pr...
Best practices for API versioning? [closed]
... human intervention should be able to continue to work like that).
Furthermore, since embedding of API version into the URI would disrupt the concept of hypermedia as the engine of application state (stated in Roy T. Fieldings PhD dissertation) by having a resource address/URI that would change ove...
MySQL “incorrect string value” error when save unicode string in Django
...f 255 and some kind of index on it (e.g. unique). Because utf8mb4 uses 33% more space than utf-8 you'll need to make these fields 33% smaller.
In this case, change the max_length from 255 to 191.
Alternatively you can edit your MySQL configuration to remove this restriction but not without some ...
How to create a self-signed certificate for a domain name for development?
...t for makecert.exe to be in my path. For the certificates I thought I'd be more secure and use -a SHA512 -len 8192 -- it took forever to generate. And as I suspected it might, it had zero impact on what level of encryption IIS used. By default IIS uses 128-bit, you have to do group policy stuff to c...
Difference between EXISTS and IN in SQL?
...e [field] in (1, 2, 3)
When you have a table in an in statement it makes more sense to use a join, but mostly it shouldn't matter. The query optimiser should return the same plan either way. In some implementations (mostly older, such as Microsoft SQL Server 2000) in queries will always get a nest...
Remove substring from the string
...ice! "foo"
=> "foo"
a
=> "bar"
there is a non '!' version as well. More info can be seen in the documentation about other versions as well:
http://www.ruby-doc.org/core/classes/String.html#method-i-slice-21
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Why are variables “i” and “j” used for counters?
... That's a good question. I actually think that "i" might come from integer more than index. I also think it's easy to write on a chalkboard. Back in the 70's we were cautioned to be sure that we wrote our "i" and "j" in a perfectly distinctive manner. Indeed, we were told to draw our "i" exactly ...
How do I “Add Existing Item” an entire directory structure in Visual Studio?
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Tool to compare directories (Windows 7) [closed]
...is that the downloads are hosted on SourceForge which cannot be trusted anymore. One of the many articles describing their fall from grace: howtogeek.com/218764/…
– Pooks
Aug 25 '15 at 7:43
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What does pythonic mean? [closed]
...websites I often see comments that code isn't pythonic, or that there is a more pythonic way to achieve the same goal.
1 An...