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SET versus SELECT when assigning variables?
...ed then SET will assign NULL, where SELECT will not make the assignment at all (so the variable will not be changed from its previous value)
As far as speed differences - there are no direct differences between SET and SELECT. However SELECT's ability to make multiple assignments in one shot does ...
mkdir's “-p” option
...p created both, hello and goodbye
This means that the command will create all the directories necessaries to fulfill your request, not returning any error in case that directory exists.
About rlidwka, Google has a very good memory for acronyms :). My search returned this for example: http://www.cs...
Sending and Parsing JSON Objects in Android [closed]
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Reference assignment operator in PHP, =&
...rror changes made to another, instead of copying the existing data.
It's called assignment by reference, which, to quote the manual, "means that both variables end up pointing at the same data, and nothing is copied anywhere".
The only thing that is deprecated with =& is "assigning the result ...
Python pandas Filtering out nan from a data selection of a column of strings
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Just drop them:
nms.dropna(thresh=2)
this will drop all rows where there are at least two non-NaN.
Then you could then drop where name is NaN:
In [87]:
nms
Out[87]:
movie name rating
0 thg John 3
1 thg NaN 4
3 mol Graham NaN
4 lob N...
More elegant “ps aux | grep -v grep”
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brilliant hack (I think I should call it that, since the aux / grep authors probably did not think of this scenario.)
– Michael Trouw
Apr 12 '16 at 14:12
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Select records from NOW() -1 Day
... MySQL statement to order records (through a date stamp) by >= NOW() -1 so all records from the day before today to the future are selected?
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How to revert to origin's master branch's version of file
...hen:
git checkout origin/master filename
Assuming you want to blow away all commits from your branch (VERY DESTRUCTIVE):
git reset --hard origin/master
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Return from lambda forEach() in java
...ching player from the (ordered) stream but simply any matching item. This allows for better efficiency when there's parallelism involved.
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“git pull” or “git merge” between master and development branches
...nges. I need to merge changes from master into develop , but will eventually merge everything from develop into master . I have two different workflows in mind:
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