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MySQL Orderby a number, Nulls last
... tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://troels.arvin.dk/db/rdbms#select-order_by
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When is std::weak_ptr useful?
...want to keep them in memory, so you hold a strong pointer to them. Periodically, you scan the cache and decide which objects have not been accessed recently. You don't need to keep those in memory, so you get rid of the strong pointer.
But what if that object is in use and some other code holds a s...
To ARC or not to ARC? What are the pros and cons? [closed]
...t has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)
OK, now I will...
C# Regex for Guid
...{12}[)}]?$",
"'$0'");
This matches the following styles, which are all equivalent and acceptable formats for a GUID.
ca761232ed4211cebacd00aa0057b223
CA761232-ED42-11CE-BACD-00AA0057B223
{CA761232-ED42-11CE-BACD-00AA0057B223}
(CA761232-ED42-11CE-BACD-00AA0057B223)
Update 1
@NonStatic mak...
MySQL check if a table exists without throwing an exception
...PDO syntax for it, but this seems pretty straight-forward:
$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;
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Portable way to get file size (in bytes) in shell?
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One would guess the portable ls -ln FILE | { read _ _ _ _ size _ && echo "$size"; } needs not fork for the second step of the pipeline, as it uses just built-ins, but Bash 4.2.37 on Linux forks twice (still only one execve, though).
– Palec
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How to parse JSON in Scala using standard Scala classes?
... {
"languages": [{
"name": "English",
"is_active": true,
"completeness": 2.5
}, {
"name": "Latin",
"is_active": false,
"completeness": 0.9
}]
}
""".stripMargin
val result = for {
Some(M(m...
What is the aspnet_client folder for under the IIS structure?
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In addition to what others have said, it's usually created by the aspnet_regiis tool, which can be (re-)run by things like Windows Update/AddRemove Windows components/IIS. So sometimes even if you do delete it, it can come back randomly. There may be a way to stop this ...
How to find first element of array matching a boolean condition in JavaScript?
... var result = null;
arr.some(function(el, i) {
return test.call(ctx, el, i, arr) ? ((result = el), true) : false;
});
return result;
}
var result = find(someArray, isNotNullNorUndefined);
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Where is my .vimrc file?
I have been using Vim , and I would really like to save my settings. The problem I am having is that I cannot find my .vimrc file, and it is not in the standard /home/user/.vimrc location. How might I find this file?
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