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What are the options for storing hierarchical data in a relational database? [closed]
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My favorite answer is as what the first sentence 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 frightful...
Why is a boolean 1 byte and not 1 bit of size?
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Reading a single bit in a bit vector requires three operations: shift, and, and another shift again. Writing is two. Whereas individual bytes can be accessed with a single one.
– sukru
J...
What is the most efficient way to create HTML elements using jQuery?
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personally i'd suggest (for readability):
$('<div>');
some numbers on the suggestions so far (safari 3.2.1 / mac os x):
var it = 50000;
var start = new Date().getTime();
for (i = 0; i < it; ++i) {
// test creation of an element
// se...
Is Python interpreted, or compiled, or both?
... to stop nitpicking and answer the question you meant to ask: Practically (read: using a somewhat popular and mature implementation), Python is compiled. Not compiled to machine code ahead of time (i.e. "compiled" by the restricted and wrong, but alas common definition), "only" compiled to bytecode,...
What is the relation between BLAS, LAPACK and ATLAS
...GNU compilers (gcc, g++ and gfortran). I have made MakeFiles which you can read to learn how you can call individual Fortran/FORTRAN routines in a C or C++ program. I have also put some installations instructions for mac and linux (sorry windows guys!). I have also made some bash .sh files for autom...
Change default timeout for mocha
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By default Mocha will read a file named test/mocha.opts that can contain command line arguments. So you could create such a file that contains:
--timeout 5000
Whenever you run Mocha at the command line, it will read this file and set a timeout ...
Passing arguments to C# generic new() of templated type
...arameters, we need to generate an array
// of parameters that will be read from the initialize object array argument.
var constructorParameters = parameters.Select((paramType, index) =>
// convert the object[index] to the right constructor parameter type.
Expression.Conve...
What requirement was the tuple designed to solve?
... While tuples are useful, one big drawback is clarity. It's hard to read and understand code that refers to Item1, Item2, etc... If tuples ever do achieve language support in C#, it would be wonderful to allow their members to be named (or at least aliased) in manner that allows code that use...
'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine
... I'm using VS 2008 (don't ask) and this solution didn't work until I read post_erasmus' tip and set 'Platform Target' to x64 in Properties >> Build >> General configuration of my application. Sorted, thanks!
– Resource
Aug 13 '15 at 9:33
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Hidden Features of VB.NET?
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Wow! I just read this and put it to use immediately to simplify a try/catch block I just wrote last week. I never new this existed.
– John M Gant
Jun 2 '09 at 16:14
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