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Common MySQL fields and their appropriate data types
...g up a very small MySQL database that stores, first name, last name, email and phone number and am struggling to find the 'perfect' datatype for each field. I know there is no such thing as a perfect answer, but there must be some sort of common convention for commonly used fields such as these. For...
How to find gaps in sequential numbering in mysql?
...lues were imported from another system. There is an auto-increment column, and there are no duplicate values, but there are missing values. For example, running this query:
...
std::vector performance regression when enabling C++11
...ode the generated code is significantly more cluttered than for C++98 mode and inlining the function
void std::vector<Item,std::allocator<Item>>::_M_emplace_back_aux<Item>(Item&&)
fails in C++11 mode with the default inline-limit.
This failed inline has a domino effect. N...
What's the best way to send a signal to all members of a process group?
...se if the tree is the result of forking from a server start or a shell command line.) You can discover process groups using GNU ps as follows:
ps x -o "%p %r %y %x %c "
If it is a process group you want to kill, just use the kill(1) command but instead of giving it a process number, give it th...
How to find where gem files are installed
...PATHS are only used first one. Is that right?
– ironsand
Sep 28 '13 at 22:27
10
gem env for short...
How to initialize an array's length in JavaScript?
...he tutorials that I've read on arrays in JavaScript (including w3schools and devguru ) suggest that you can initialize an array with a certain length by passing an integer to the Array constructor using the var test = new Array(4); syntax.
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What is the difference between Ruby 1.8 and Ruby 1.9
...m not clear on the differences between the "current" version of Ruby (1.8) and the "new" version (1.9). Is there an "easy" or a "simple" explanation of the differences and why it is so different?
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How to calculate the SVG Path for an arc (of a circle)
...t (200,200), radius 25, how do I draw an arc from 270 degree to 135 degree and one that goes from 270 to 45 degree?
13 Answ...
Turn a number into star rating display using jQuery and CSS
I have been looking at jquery plugin and was wondering how to adapt that plugin to turn a number (like 4.8618164) into a 4.8618164 stars filled out of 5. Basically interpreting a number
...
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 ...