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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 * ...
How to generate sample XML documents from their DTD or XSD?
...answered Aug 26 '08 at 14:05
levandlevand
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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...
Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x
...
Just follows these steps:
Go to Control Panel → Program and Feature.
Click on Turn Window Features on and off. A window opens.
Uncheck Hyper-V and Windows Hypervisor Platform options and restart your system.
Now, you can Start HAXM installation without any error.
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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 ...
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 ...
AngularJs “controller as” syntax - clarification?
...here a property comes from is really useful too.
You can nest controllers and when reading the html it is pretty clear where every property comes.
You can also avoid some of the dot rule problems.
For example, having two controllers, both with the same name 'name', You can do this:
<body ng-c...
What is the difference between a map and a dictionary?
... values. Isn't a dictionary the same? What is the difference between a map and a dictionary 1 ?
11 Answers
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JavaScript: client-side vs. server-side validation
...k to the average user. For example, if they enter an invalid email address and move to the next field, you can show an error message immediately. That way the user can correct every field before they submit the form.
If you only validate on the server, they have to submit the form, get an error mes...
How does `scp` differ from `rsync`?
...n these tools is how they copy files.
scp basically reads the source file and writes it to the destination. It performs a plain linear copy, locally, or over a network.
rsync also copies files locally or over a network. But it employs a special delta transfer algorithm and a few optimizations to m...