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Postgres: INSERT if does not exist already
...nd, also known as an ON CONFLICT clause to INSERT:
INSERT ... ON CONFLICT DO NOTHING/UPDATE
It solves many of the subtle problems you can run into when using concurrent operation, which some other answers propose.
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Calling the base constructor in C#
...nstructor of the inherited class to the constructor of the base class, how do I do that?
12 Answers
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How do I trigger the success callback on a model.save()?
...the server which handles the save, but the success callback is not fired. Do I need to send something back from the server ?
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How do I list all cron jobs for all users?
...ld have to run this as root, but:
for user in $(cut -f1 -d: /etc/passwd); do crontab -u $user -l; done
will loop over each user name listing out their crontab. The crontabs are owned by the respective users so you won't be able to see another user's crontab w/o being them or root.
Edit
if you...
How do I get a Cron like scheduler in Python? [closed]
...t time
def job():
print("I'm working...")
schedule.every(10).minutes.do(job)
schedule.every().hour.do(job)
schedule.every().day.at("10:30").do(job)
while 1:
schedule.run_pending()
time.sleep(1)
Disclosure: I'm the author of that library.
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How do you convert a jQuery object into a string?
How do you convert a jQuery object into a string?
12 Answers
12
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Do I need all three constructors for an Android custom view?
When creating a custom view, I have noticed that many people seem to do it like this:
6 Answers
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Why are local variables not initialized in Java?
...sly, if instance variables can be given a default value, then why can't we do the same for local variables?
15 Answers
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How to modify a text file?
... a string into a text file without deleting or copying the file. How can I do that?
8 Answers
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How to loop over directories in Linux?
...nd -mindepth 1 make sure that find only looks in the current directory and doesn't include . itself in the result
-type d looks only for directories
-printf '%f\n prints only the found folder's name (plus a newline) for each hit.
Et voilà!
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