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INNER JOIN vs LEFT JOIN performance in SQL Server
...not been discussed yet.
When using an outer join, the optimizer is always free to drop the outer joined table from the execution plan if the join columns are the PK of the outer table, and none of the outer table columns are referenced outside of the outer join itself. For example SELECT A.* FROM A...
Shared-memory objects in multiprocessing
... utility class to work around it.
I'm using multiprocessing.RawArray (lockfree), and also the access to the arrays is not synchronized at all (lockfree), be careful not to shoot your own feet.
With the solution I get speedups by a factor of approx 3 on a quad-core i7.
Here's the code:
Feel free t...
Proper MIME media type for PDF files
...to have other versions of answers, so that it will provide some additional info for one who search the topic. Also, he quoted some additional info, while compared to other answers.
– sunil
Aug 13 '18 at 13:51
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Interfaces vs. abstract classes [duplicate]
...led
Ability to provide behavior related or unrelated to the interface for "free"
Interfaces are merely data passing contracts and do not have these features. However, they are typically more flexible as a type can only be derived from one class, but can implement any number of interfaces.
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Xcode 4 hangs at “Attaching to (app name)”
...the program stops at "Attaching to...". There doesn't seem to be any other info to help with this problem either.
57 Answer...
TextEnhancer拓展 - 增强App中的文本格式 - App Inventor 2 拓展 - 清泛IT社区，为创新赋能！
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[size=15.008px]https://community.appinventor.mit.edu/t/free-textenhancer-enhance-text-formatting-in-your-app/111213
C++ - passing references to std::shared_ptr or boost::shared_ptr
...o an existing shared_ptr.
The downside is that copied a shared_ptr is not free: even "lock-free" implementations have to use an interlocked operation to honour threading guarantees. So there may be situations where a program can be significantly sped up by changing a shared_ptr into a shared_ptr &a...
eclipse stuck when building workspace
...metadata/.log). If that doesn't help, you'll probably need to include more info about which plugins you have installed and which projects you have. Can you create a minimal workspace which reproduces the problem?
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getting the screen density programmatically in android?
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You can get info on the display from the DisplayMetrics struct:
DisplayMetrics metrics = getResources().getDisplayMetrics();
Though Android doesn't use a direct pixel mapping, it uses a handful of quantized Density Independent Pixel v...
Reading HTML content from a UIWebView
...g, is somewhat ambiguous, and the docs don't say much about it).
For more info:
UIWebView class reference
NSString class reference
NSURL class reference
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