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What does it mean when MySQL is in the state “Sending data”?
...ory) which is yet to be read and sent over. It may be the table itself, an index, a temporary table, a sorted output etc.
If you have a 1M records table (without an index) of which you need only one record, MySQL will still output the status as "sending data" while scanning the table, despite the f...
In-memory size of a Python structure
...p.heap()
Partition of a set of 25853 objects. Total size = 3320992 bytes.
Index Count % Size % Cumulative % Kind (class / dict of class)
0 11731 45 929072 28 929072 28 str
1 5832 23 469760 14 1398832 42 tuple
2 324 1 277728 8 1676560 50 dict (n...
Condition within JOIN or WHERE
...ditions in join improve performance for large amount of data with properly indexed tables.
– Shahdat
Oct 6 '16 at 15:13
...
Reason to Pass a Pointer by Reference in C++?
...n fact natural) signature for this would be const T &operator[](size_t index) const. But you could also have T &operator[](size_t index). You could have both at the same time. The latter would let you do things like myArray[jj] = 42. At the same time, you aren't providing a pointer to your d...
How to get JavaScript caller function line number? How to get JavaScript caller source URL?
...ar err = getErrorObject();
var caller_line = err.stack.split("\n")[4];
var index = caller_line.indexOf("at ");
var clean = caller_line.slice(index+2, caller_line.length);
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Changing the image source using jQuery
...s that number with how many images there are. This will keep the resultant index cycling from 0 to length-1, which are the indices of the $images object. This means this code will work with 2, 3, 5, 10, or 100 images... cycling through each image in order and restarting at the first image when the l...
Apply pandas function to column to create multiple new columns?
...ol.apply(lambda s: pd.Series({'feature1':s+1, 'feature2':s-1})),
left_index=True, right_index=True)
textcol feature1 feature2
0 0.772692 1.772692 -0.227308
1 0.857210 1.857210 -0.142790
2 0.065639 1.065639 -0.934361
3 0.819160 1.819160 -0.180840
4 0.088212 1.088212 -0.911788
...
How do I integrate Ajax with Django applications?
...esponse('Hello World!')
def home(request):
return render_to_response('index.html', {'variable': 'world'})
index.html:
<h1>Hello {{ variable }}, welcome to my awesome site</h1>
urls.py:
url(r'^hello/', 'myapp.views.hello'),
url(r'^home/', 'myapp.views.home'),
That's an exampl...
HTML encoding issues - “” character showing up instead of “ ”
...ntually I remembered I had been having problems with links relative to the index file, when the pages, if viewed directly would work with slideshows, but not when used with an include (but that's beside the point. Anyway I wondered if this might be a similar problem, so instead of putting into the...
How to delete history of last 10 commands in shell?
..., so negative indices count back from the end of the
history, and an index of '-1' refers to the current 'history
-d' command.
'-d START-END'
Delete the history entries between positions START and END,
inclusive. Positive and negative values for START and END are
...