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What is the most efficient/elegant way to parse a flat table into a tree?
...rsive queries in MySQL 8.0 in my presentation Recursive Query Throwdown in 2017.
Below is my original answer from 2008:
There are several ways to store tree-structured data in a relational database. What you show in your example uses two methods:
Adjacency List (the "parent" column) and
Pa...
Resizing an Image without losing any quality [closed]
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answered Sep 17 '08 at 21:20
Kris EricksonKris Erickson
31.9k2626 gold badges113113 silver badges167167 bronze badges
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What is the preferred syntax for defining enums in JavaScript?
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This is the right answer now in 2012. More simple: var DaysEnum = Object.freeze ({ monday: {}, tuesday: {}, ... });. You don't need to specify an id, you can just use an empty object to compare enums. if (incommingEnum === DaysEnum.monday) //incommingEnum i...
How to execute Python scripts in Windows?
...e\shell\open\command
to the same value. See http://eli.thegreenplace.net/2010/12/14/problem-passing-arguments-to-python-scripts-on-windows/
HKEY_CLASSES_ROOT\Applications\python.exe\shell\open\command The registry path may vary, use python26.exe or python.exe or whichever is already in the regis...
How to get the current time in Python
...gt; import datetime
>>> datetime.datetime.now()
datetime.datetime(2009, 1, 6, 15, 8, 24, 78915)
>>> print(datetime.datetime.now())
2009-01-06 15:08:24.789150
And just the time:
>>> datetime.datetime.now().time()
datetime.time(15, 8, 24, 78915)
>>> print(datet...
Genymotion, “Unable to load VirtualBox engine.” on Mavericks. VBox is setup correctly
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Closest thing I can find on El Capitan with VBox 4.3.20 is sudo /Library/Application\ Support/VirtualBox/LaunchDaemons/VirtualBoxStartup.sh restart, which returns among other things the error: /Library/Application Support/VirtualBox/VBoxDrv.kext failed to load - (libkern/kext) ...
Map function in MATLAB?
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answered Jun 11 '09 at 20:17
kwatfordkwatford
20.1k22 gold badges3737 silver badges6060 bronze badges
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What method in the String class returns only the first N characters?
...Result; }
– Grandizer
Feb 21 '18 at 20:01
str needs to be checked for null
– liviriniu
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How can I fill out a Python string with spaces?
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20
@simon 's answer is more flexible and more useful when formatting more complex strings
– CoatedMoose
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How can I tell where mongoDB is storing data? (its not in the default /data/db!)
...nt the current path precisely for all mongodb version stackoverflow.com/a/52036070/248616
– Nam G VU
Jun 2 '19 at 10:51
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