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MySQL get the date n days ago as a timestamp
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DATE_SUB will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day);
2009-06-07 21:55:09
mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
2009-06-07 21:55:09
mysql> SELECT U...
How to delete items from a dictionary while iterating over it?
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Traceback (most recent call last):
File "<ipython console>", line 1, in <module>
RuntimeError: dictionary changed size during iteration
As stated in delnan's answer, deleting entries causes problems when the iterator tries to move on...
If threads share the same PID, how can they be identified?
... +---------+
| process |
_| pid=42 |_
_/ | tgid=42 | \_ (new thread) _
_ (fork) _/ +---------+ \
/ +---------+
+---------+ | ...
Check if a value is an object in JavaScript
...o examine variable's properties, but it is not a bulletproof recipe (after all there's no recipe at all!) for checking whether it's an object, far from it. Since people tend to look for something to copy from here without doing any research, I'd highly recommend that they turn to the other, most upv...
What is Scala's yield?
...I use yield instead of map? This map code is equivalent val res = args.map(_.toUpperCase) , right?
– Geo
Jun 27 '09 at 12:23
4
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Is a Python list guaranteed to have its elements stay in the order they are inserted in?
...answer so I don't want to add another. He could also use list.append to really put his mind at ease. docs.python.org/2/tutorial/datastructures.html
– NG.
Dec 4 '12 at 0:15
1
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Is an entity body allowed for an HTTP DELETE request?
...uest URI should completely identify the resource to delete. However, is it allowable to add extra meta-data as part of the entity body of the request?
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How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
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indexOf method in an object array?
... think to see the performance of this method vs. a simple for loop. Especially when you're running on a mobile platform with limited resources.
– Doug
Aug 17 '15 at 5:51
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Get difference between 2 dates in JavaScript? [duplicate]
...day. As for always returning a positive number, that was a feature :) Typically when one talks about the number of days between two dates, that number is positive. If direction matters, just remove the Math.abs().
– TNi
Jul 11 '10 at 22:38
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