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Postgres: INSERT if does not exist already
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Postgres 9.5 (released since 2016-01-07) offers an "upsert" command, 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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Checking Bash exit status of several commands efficiently
Is there something similar to pipefail for multiple commands, like a 'try' statement but within bash. I would like to do something like this:
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What is a rune?
...in that range. Furthermore, 32 is in fact the offset between the uppercase and lowercase codepoint of the character. So by adding 32 to 'A', you get 'a' and vice versa.
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Getting distance between two points based on latitude/longitude
I tried implementing this formula: http://andrew.hedges.name/experiments/haversine/
The aplet does good for the two points I am testing:
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How do I append one string to another in Python?
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If you only have one reference to a string and you concatenate another string to the end, CPython now special cases this and tries to extend the string in place.
The end result is that the operation is amortized O(n).
e.g.
s = ""
for i in range(n):
s+=str(i)
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How to prepare a Unity project for git? [duplicate]
... eg. github? I don't want to store unnecessary files (specially temp files and avoid binary formats as much as possible).
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Focusable EditText inside ListView
I've spent about 6 hours on this so far, and been hitting nothing but roadblocks. The general premise is that there is some row in a ListView (whether it's generated by the adapter, or added as a header view) that contains an EditText widget and a Button . All I want to do is be able to use t...
Difference between Iterator and Listiterator?
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And the reason why you can't do that with a Set is simple: There is not "current point": Elements have no index and there is no usefull way you can add an element "before" or "after" another one.
– Joach...
PHP cURL not working - WAMP on Windows 7 64 bit
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Go to http://www.anindya.com/php-5-4-3-and-php-5-3-13-x64-64-bit-for-windows/ and download the cURL version that corresponds to your PHP version under "Fixed curl extensions:".
So if you have PHP 5.3.13, download "php_curl-5.3.13-VC9-x64.zip". Try the "VC" versio...
How can I run a function from a script in command line?
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If the script only defines the functions and does nothing else, you can first execute the script within the context of the current shell using the source or . command and then simply call the function. See help source for more information.
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