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MySQL, better to insert NULL or empty string?
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How many characters can UTF-8 encode?
..., Coptic, Armenian, Hebrew, Arabic, Syriac and Tāna alphabets, as well as Combining Diacritical Marks.
Three bytes are needed for characters in the rest of the Basic Multilingual Plane, which contains virtually all characters in common use[12] including most Chinese, Japanese and Korean [CJK] ...
getting date format m-d-Y H:i:s.u from milliseconds
...s",$date_array[1]);
echo "Date: $date:" . $date_array[0]."<br>";
Recommended and use dateTime() class from referenced:
$t = microtime(true);
$micro = sprintf("%06d",($t - floor($t)) * 1000000);
$d = new DateTime( date('Y-m-d H:i:s.'.$micro, $t) );
print $d->format("Y-m-d H:i:s.u"); // ...
Painless way to install a new version of R?
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Just for completeness, there are some ways to prevent you from having this problem. As Dirk said, save your packages in another directory on your computer.
install.packages("thepackage",lib="/path/to/directory/with/libraries")
You...
What's the difference between session.Merge and session.SaveOrUpdate?
...ance
the persistent instance is returned
the given instance does not become associated with the session, it
remains detached
You should use Merge() if you are trying to update objects that were at one point detached from the session, especially if there might be persistent instances of t...
When is it appropriate to use C# partial classes?
...ner would spit out all of the code inside of a region with strongly worded comments about not modifying the code. It had to insert all sorts of heuristics to find the generated code for later processing. Now it can simply open the designer.cs file and have a high degree of confidence that it contai...
How to create a directory if it doesn't exist using Node.js?
...when it tries writing to files in it. The answer by @josh3736 is much more complete and totally underrated.
– Benni
Jan 15 '19 at 7:59
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How do I calculate percentiles with python/numpy?
... You can use it as an aggregation function as well, e.g. to compute the tenth percentile of each group of a value column by key, use df.groupby('key')[['value']].agg(lambda g: np.percentile(g, 10))
– patricksurry
Nov 26 '13 at 17:25
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How do you rename a MongoDB database?
...n the future)
other locations I may be missing
This is just to accomplish a rename of a single database in a standalone mongod instance. For replica sets the above would need to be done on every replica node, plus on each node every single oplog entry that refers this database would have t...