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Shell command to tar directory excluding certain files/folders
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The ordering of parameters seems to matter and this form works for me.
– cstamas
Oct 1 '18 at 12:33
1
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MySQL pagination without double-querying?
... problem with this: There is a bug in MySQL that this tickles that affects ORDER BY queries making it much slower on large tables than the naive approach of two queries.
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Laravel orderBy on a relationship
...p
public function comments()
{
return $this->hasMany('Comment')->orderBy('column');
}
[edit after comment]
<?php
class User
{
public function comments()
{
return $this->hasMany('Comment');
}
}
class Controller
{
public function index()
{
$colum...
Lock, mutex, semaphore… what's the difference?
...task to another. A mutex is meant to be taken and released, always in that order, by each task that uses the shared resource it protects. By contrast, tasks that use semaphores either signal or wait—not both."
– ToolmakerSteve
Feb 2 '17 at 5:14
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What is `related_name` used for in Django?
...his data
you only can use related name
bom = material.tomaterial.all().order_by('-creation_time')
It is not working otherwise (at least I was not able to skip the usage of related name in case of 2 FK's to the same table.)
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Increasing (or decreasing) the memory available to R processes
...lled and
subsequently install more RAM, you may
have to reinstall R in order to take
advantage of the additional capacity.
You may also set the amount of
available memory manually. Close R,
then right-click on your R program
icon (the icon on your desktop or in
your programs dire...
How to combine multiple conditions to subset a data-frame using “OR”?
... I intended, since ...
> NA & 1
[1] NA
> 0 & NA
[1] FALSE
Order of arguments may matter when using '&".
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Why can't enum's constructor access static fields?
... (including those representing the enum values) are initialized in textual order, and the enum values always come before the other fields. Note that in your class example you haven't shown where ABBREV_MAP is initialized - if it's after SUNDAY, you'll get an exception when the class is initialized.
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Clicking the back button twice to exit an activity
...urn;
}
else { Toast.makeText(getBaseContext(), "Tap back button in order to exit", Toast.LENGTH_SHORT).show(); }
mBackPressed = System.currentTimeMillis();
}
Back on accepted answer critique; Using a flag to indicate if it was pressed in last TIME_INTERVAL (say 2000) milliseconds an...
Are static class variables possible in Python?
...ges (e.g. Java or c++). You should go study the property object, about the order in which Python attributes are returned, the descriptor protocol, and the method resolution order (MRO).
I present a solution to the above 'gotcha' below; however I would suggest - strenuously - that you do not try to...