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What are the options for storing hierarchical data in a relational database? [closed]
...in this thread suggested. Use an Adjacency List to maintain the hierarchy and use Nested Sets to query the hierarchy.
The problem up until now has been that the coversion method from an Adjacecy List to Nested Sets has been frightfully slow because most people use the extreme RBAR method known as ...
What are the differences between the threading and multiprocessing modules?
I am learning how to use the threading and the multiprocessing modules in Python to run certain operations in parallel and speed up my code.
...
Multiple left-hand assignment with JavaScript
...e right most before the left most. so var var1=var2 happens after var3 = 1 and after var2 = var3. it's like var3=1; var2=var3; var var1=var2
– gcb
Jan 29 '13 at 18:51
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How to convert byte array to string and vice versa?
I have to convert a byte array to string in Android, but my byte array contains negative values.
22 Answers
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How do I find a “gap” in running counter with SQL?
...n a counter column in an SQL table. For example, if there are values 1,2,4 and 5 I'd like to find out 3.
20 Answers
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Print all but the first three columns
...$(i-2)=$i; NF=NF-2; print $0}' | tr ' ' '-'
3-4-5-6-7
This is the fixed and parametrized version of larsr solution:
$ echo '1 2 3 4 5 6 7' |
awk '{for(i=n;i<=NF;i++)$(i-(n-1))=$i;NF=NF-(n-1);print $0}' n=4 | tr ' ' '-'
4-5-6-7
All other answers before Sep-2013 are nice but add extra spac...
Controlling fps with requestAnimationFrame?
...e for the most part, but right now I'm trying to do some canvas animations and I was wondering: Is there any way to make sure it runs at a certain fps? I understand that the purpose of rAF is for consistently smooth animations, and I might run the risk of making my animation choppy, but right now it...
Generate random password string with requirements in javascript
I want to generate a random string that has to have 5 letters from a-z and 3 numbers.
18 Answers
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Mapping two integers to one, in a unique and deterministic way
Imagine two positive integers A and B. I want to combine these two into a single integer C.
18 Answers
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Is it safe to use -1 to set all bits to true?
...times have surprising behavior because you will have to have the right operand type. Only then you will get the most high value of an unsigned type.
For an example of a possible surprise, consider this one:
unsigned long a = ~0u;
It won't necessarily store a pattern with all bits 1 into a. But ...