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Copy values from one column to another in the same table
... set str = '';
WHILE x < 5 DO
set str = (select source_col from emp where id=x);
update emp set target_col =str where id=x;
SET x = x + 1;
END WHILE;
END$$
DELIMITER ;
...
Java's Interface and Haskell's type class: differences and similarities?
... class to other classes, define static methods and constructors that would select an implementation based on what return type is required in calling context, define methods that take arguments of the same type as the class implementing the interface, and various other things that don't really transl...
Parsing JSON with Unix tools
...s is format the JSON, if I'm not mistaken. It does not allow the caller to select a particular field from the output, as would an xpath solution, or something based on "JSON Pointer".
– Cheeso
Jun 4 '14 at 0:42
...
How do you sort an array on multiple columns?
...lso sort the second attribute. Unless you loop it as many as the number of selected columns.. Am I right? e.g. [[A, 10], [J, 15], [A, 5], [J, 5]] => [[A, 10], [A, 5], [J, 15], [J, 5]]
– Bla...
Apr 23 '15 at 2:30
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Is there a NumPy function to return the first index of something in an array?
...st element. Note also that where and nonzero return arrays, so you need to select the first element to get the index.
In [71]: np.argmax(a==2)
Out[71]: 2
In [72]: np.where(a==2)
Out[72]: (array([2], dtype=int64),)
In [73]: np.nonzero(a==2)
Out[73]: (array([2], dtype=int64),)
Time comparison
Ju...
How can I determine the type of an HTML element in JavaScript?
...eof HTMLInputElement) {} // <input>
elseif (e instanceof HTMLSelectElement) {} // <select>
elseif (e instanceof HTMLTextAreaElement) {} // <textarea>
elseif ( ... ) {} // any interface
Look here for a complete list of interfaces.
...
Debugging Scala code with simple-build-tool (sbt) and IntelliJ
...
Enter whatever name you want, and click the "Run SBT Action" checkbox and select the SBT Action jetty-run from the [...]
Create a debug configuration for remote debugging
Go to Run > Edit Configurations
Click the [+] icon and choose Remote
Enter whatever name you want and copy the line -Xdebu...
How to install packages offline?
...r you don't need to use sudo pip….
2) use virtualenv
on online machine select a directory with terminal cd and run this code:
python -m virtualenv myenv
cd myenv
source bin/activate
pip install Flask
after installing all the packages, you have to generate a requirements.txt so while your virt...
Fork and synchronize Google Code Subversion repository into GitHub
...h. To do this, create a Launchpad project, then go to the new import page, select Subversion and enter the URL (e.g. http://projectname.googlecode.com/svn/trunk/). Depending on the project size, the initial import can take up to a few hours. Subsequent imports will run periodically.
For more docume...
How to grep for two words existing on the same line? [duplicate]
...if performance really matters. If you run two commands, you should aim to select the less frequently occurring word in the first grep to minimize the amount of data processed by the second.
Diagnosis
The initial script is:
grep -c "word1" | grep -r "word2" logs
This is an odd command sequence....