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What are the differences between B trees and B+ trees?
... fit on a page of memory. Therefore, it will require fewer cache misses in order to access data that is on a leaf node.
The leaf nodes of B+ trees are linked, so doing a full scan of all objects in a tree requires just one linear pass through all the leaf nodes. A B tree, on the other hand, would re...
Finding duplicate rows in SQL Server
...CT
orgName, id,
ROW_NUMBER() OVER (PARTITION BY orgName ORDER BY id) AS intRow
FROM organizations
) AS d
WHERE intRow != 1
Edit: SQL Server 2000 doesn't have the ROW_NUMBER() function. Instead, you can use:
SELECT
o.id, o.orgName, d.intCount
FROM (
SELECT orgName,...
Check if string begins with something? [duplicate]
... documentation websites actually tell you to avoid it if possible (I think php.net does, for example). I'd recommend the indexOf() or substr() solutions.
– Byson
Dec 22 '14 at 14:59
...
How to suppress “unused parameter” warnings in C?
...
I usually write a macro like this:
#define UNUSED(x) (void)(x)
You can use this macro for all your unused parameters. (Note that this works on any compiler.)
For example:
void f(int x) {
UNUSED(x);
...
}
...
Why are Python's 'private' methods not actually private?
...
The name scrambling is used to ensure that subclasses don't accidentally override the private methods and attributes of their superclasses. It's not designed to prevent deliberate access from outside.
For example:
>>> class Foo(object):
... def __init__(self):
... self....
How to run cron job every 2 hours
...into crontab :
crontab -e
write this into the file:
0 */2 * * * python/php/java yourfilepath
Example :0 */2 * * * python ec2-user/home/demo.py
and make sure you have keep one blank line after the last cron job in your crontab file
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Inheritance and Overriding __init__ in python
...
The book is a bit dated with respect to subclass-superclass calling. It's also a little dated with respect to subclassing built-in classes.
It looks like this nowadays:
class FileInfo(dict):
"""store file metadata"""
def __init__(self, filename=None):
super(FileInfo,...
Filter by property
...to Python to evaluate the property--and at that point, you've already done all the work to load it.
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How can you set class attributes from variable arguments (kwargs) in python
...riable number of arguments and then sets them as class attributes conditionally.
10 Answers
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CSS last-child(-1)
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Unless you can get PHP to label that element with a class you are better to use jQuery.
jQuery(document).ready(function () {
$count = jQuery("ul li").size() - 1;
alert($count);
jQuery("ul li:nth-child("+$count+")").css("color","red");
}...