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How to delete large data of table in SQL without log?
...ty the table, you cannot use WHERE clause to limit the rows being deleted and no triggers will be fired.
On the other hand if you are deleting more than 80-90 Percent of the data, say if you have total of 11 Million rows and you want to delete 10 million another way would be to Insert these 1 mill...
Installing Ruby Gem in Windows
...ckage management system of your
distribution or third-party tools (rbenv and RVM).
On OS X machines, you can use third-party tools (rbenv and RVM).
On Windows machines, you can use RubyInstaller.
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How many system resources will be held for keeping 1,000,000 websocket open? [closed]
Websocket is good, but would it be able to handle 1,000,000 concurrent connections?
How many system resources will be held for keeping 1,000,000 websocket open?
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Make $JAVA_HOME easily changable in Ubuntu [closed]
In Ubuntu, I'd like to switch my JAVA_HOME environment variable back and forth between Java 5 and 6.
8 Answers
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Saving interactive Matplotlib figures
Is there a way to save a Matplotlib figure such that it can be re-opened and have typical interaction restored? (Like the .fig format in MATLAB?)
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Finding duplicate values in a SQL table
...T(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attrib...
Can the Unix list command 'ls' output numerical chmod permissions?
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For creating it as an alias (example below: 'cls' command), use: alias cls="ls -l | awk '{k=0;for(i=0;i<=8;i++)k+=((substr(\$1,i+2,1)~/[rwx]/)*2^(8-i));if(k)printf(\"%0o \",k);print}'"
– danger89
Mar 6 '14 at 16:15
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Finding all possible combinations of numbers to reach a given sum
...])=15
This type of algorithms are very well explained in the following Standford's Abstract Programming lecture - this video is very recommendable to understand how recursion works to generate permutations of solutions.
Edit
The above as a generator function, making it a bit more useful. Require...
What is the difference between currying and partial application?
...rn value is a closure of lambda(z){z(x(y))} with passed-in the values of x and y to f(x,y).
One way to use partial application is to define functions as partial applications of generalized functions, like fold:
function fold(combineFunction, accumulator, list) {/* ... */}
function sum = curry...
Why not use java.util.logging?
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Disclaimer: I am the founder of log4j, SLF4J and logback projects.
There are objective reasons for preferring SLF4J. For one, SLF4J allows the end-user the liberty to choose the underlying logging framework. In addition, savvier users tend to prefer logback which offe...