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How to do a FULL OUTER JOIN in MySQL?
...oducing duplicate rows by using an anti-join pattern for the second query, and then use a UNION ALL set operator to combine the two sets. In the more general case, where a FULL OUTER JOIN would return duplicate rows, we can do this:
SELECT * FROM t1
LEFT JOIN t2 ON t1.id = t2.id
UNION ALL
SELECT * ...
Difference between CC, gcc and g++?
...t are the difference between the 3 compilers CC, gcc, g++ when compiling
C and C++ code in terms of assembly
code generation, available libraries, language features, etc.?
...
What are some resources for getting started in operating system development? [closed]
...ay the bootloader takes the machine code of the kernel, puts it in memory, and jumps to it. You can put any machine code in the kernel that you want, but most C programs expect an OS so you'll need to tell your compiler that it won't have all that, or the bootloader has to create some of it.
The k...
Best practices for styling HTML emails [closed]
...ewsletter. I've learned that many email clients ignore linked stylesheets, and many others (including Gmail) ignore CSS block declarations altogether. Are inline style attributes my only choice? What are the best practices for styling HTML emails?
...
Calendar returns wrong month [duplicate]
...
Months are indexed from 0 not 1 so 10 is November and 11 will be December.
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AI2 Media Notification
...lized with the app name. When a broadcast is received, the name is checked and only the appropriate messages are processed. Kodular now also provides many Androidx functions. Only "androidx.media.jar" has to be integrated. The Foreground service is now declared via UsesServices annotaion in ...
Which cryptographic hash function should I choose?
...Indeed, MD5 is often still used in applications where the smaller key size and speed are beneficial. That said, due to its flaws, researchers recommend the use of other hash functions in new scenarios.
SHA1 has a flaw that allows collisions to be found in theoretically far less than the 2^80 steps ...
Multithreading: What is the point of more threads than cores?
...nterruption. In reality this isn't the case. Even if you have four cores and four working threads, your process and it threads will constantly be being switched out for other processes and threads. If you are running any modern OS, every process has at least one thread, and many have more. All t...
What is the difference between atomic / volatile / synchronized?
...return counter++;
}
It basically reads value from memory, increments it and puts back to memory. This works in single thread but nowadays, in the era of multi-core, multi-CPU, multi-level caches it won't work correctly. First of all it introduces race condition (several threads can read the value...
Differences between strong and weak in Objective-C
...eference to it. Once that is no longer the case, the object gets destroyed and your weak property will automatically get set to nil. The most frequent use cases of weak references in iOS are:
delegate properties, which are often referenced weakly to avoid retain cycles, and
subviews/controls of a ...