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Importance of varchar length in MySQL table
...u can run into: Big joins are nearly impossible with long varchar columns. Indexing on those columns are a real killer. Your disk has to store the data. One memory page can hold less rows and table scans will be much slower. Also the query cache will be unlikely to help you here.
You have to ask yo...
querySelector search immediate children
... the element that is :eq() to its appearance on the page, not :eq() to the index of its parent (which is where you're getting the idx).
– user113716
Jun 26 '11 at 2:36
...
HSL to RGB color conversion
... b = l; // achromatic
}else{
var hue2rgb = function hue2rgb(p, q, t){
if(t < 0) t += 1;
if(t > 1) t -= 1;
if(t < 1/6) return p + (q - p) * 6 * t;
if(t < 1/2) return q;
if(t < 2/3) return p + (q - p) * (2/3 - t) * ...
String concatenation vs. string substitution in Python
... critical. Well, and if I need formatting, there's no need to even ask the question... there's no option but to use interpolation/templating.
>>> import timeit
>>> def so_q_sub(n):
... return "%s%s/%d" % (DOMAIN, QUESTIONS, n)
...
>>> so_q_sub(1000)
'http://stackoverflow...
Finding what methods a Python object has
... 'count', 'decode', 'encode', 'endswith', 'expandtabs', 'find',
'format', 'index', 'isalnum', 'isalpha', 'isdigit', 'islower', 'isspace',
'istitle', 'isupper', 'join', 'ljust', 'lower', 'lstrip', 'partition',
'replace', 'rfind', 'rindex', 'rjust', 'rpartition', 'rsplit', 'rstrip',
'split', 'splitlin...
html5 - canvas element - Multiple layers
...width="100" height="100"
style="position: absolute; left: 0; top: 0; z-index: 0;"></canvas>
<canvas id="layer2" width="100" height="100"
style="position: absolute; left: 0; top: 0; z-index: 1;"></canvas>
</div>
Draw your first layer on the layer1 canvas, and the...
Batch File; List files in directory, only filenames?
This is probably a very simple question, but I'm having trouble with it. Basically, I am trying to write a Batch File and I need it to list all the files in a certain directory. The dir command will do this, but it also gives a bunch of other information; I want it to list ONLY the file names an...
Should I always use a parallel stream when possible?
...y-based sources parallelize the best as the next indices (near the current index) are cached and there are fewer chances that CPU would experience a cache miss.
He also mentions a relatively simple formula to determine a chance of parallel speedup.
NQ Model:
N x Q > 10000
where,
N = number...
How to find the lowest common ancestor of two nodes in any binary tree?
...have parent pointers, an improved algorithm is possible. For both nodes in question construct a list containing the path from root to the node by starting at the node, and front inserting the parent.
So for 8 in your example, you get (showing steps): {4}, {2, 4}, {1, 2, 4}
Do the same for your ot...
How to install a specific JDK on Mac OS X?
...I went to the JDK download homepage: http://java.sun.com/javase/downloads/index.jsp .
I looked for a Mac version, but I'm a bit surprised to only see downloadable versions for Linux, Windows and Solaris ...
...