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How to create a MySQL hierarchical recursive query
... (select @pv := '19') initialisation
where find_in_set(parent_id, @pv)
and length(@pv := concat(@pv, ',', id))
Here is a fiddle.
Here, the value specified in @pv := '19' should be set to the id of the parent you want to select all the descendants of.
This will work also if a parent has m...
What is the proper way to test if a parameter is empty in a batch file?
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And using "%~1" is really a better approach, as I mentioned in my answer.
– jamesdlin
May 31 '15 at 21:08
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SQLAlchemy: What's the difference between flush() and commit()?
What the difference is between flush() and commit() in SQLAlchemy?
5 Answers
5
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How to get Ruby / Homebrew / RVM to work on Yosemite?
...requires Leopard or higher - I followed the answer below install xcode command line tools and it now works: stackoverflow.com/a/24225960/1062936
– greg
Feb 4 '15 at 23:59
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Split output of command by columns using Bash?
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And also, the field nunbers will be off if some PID:s are space padded on the left while others are not.
– tripleee
Mar 4 '15 at 14:58
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How can I check if a directory exists in a Bash shell script?
What command can be used to check if a directory exists or not, within a Bash shell script?
35 Answers
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What does the CSS rule “clear: both” do?
...th; OR what does clear: both; exactly do...
I'll keep this answer simple, and to the point, and will explain to you graphically why clear: both; is required or what it does...
Generally designers float the elements, left or to the right, which creates an empty space on the other side which allows ...
How do I get PHP errors to display?
I have checked my PHP ini file ( php.ini ) and display_errors is set and also error reporting is E_ALL . I have restarted my Apache webserver.
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PowerShell says “execution of scripts is disabled on this system.”
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If you're using Windows Server 2008 R2 then there is an x64 and x86 version of PowerShell both of which have to have their execution policies set. Did you set the execution policy on both hosts?
As an Administrator, you can set the execution policy by typing this into your PowerShell...
How can I set up an editor to work with Git on Windows?
I'm trying out Git on Windows . I got to the point of trying "git commit" and I got this error:
33 Answers
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