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MySQL - UPDATE query based on SELECT Query
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You can actually do this one of two ways:
MySQL update join syntax:
UPDATE tableA a
INNER JOIN tableB b ON a.name_a = b.name_b
SET validation_check = if(start_dts > end_dts, 'VALID', '')
-- where clause can go here
ANSI SQL syntax...
Getting SyntaxError for print with keyword argument end=' '
...print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to print with a tuple as argument.
That's obviously bad syntax (literals don't take keyword arguments). In Python 3.x print is an actual function, so it takes keyword arguments, too.
The correct idiom in Python 2.x for ...
Underscore prefix for property and method names in JavaScript
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Welcome to 2019!
It appears a proposal to extend class syntax to allow for # prefixed variable to be private was accepted. Chrome 74 ships with this support.
_ prefixed variable names are considered private by convention but are still public.
This syntax tries to be both terse and int...
PHP Composer update “cannot allocate memory” error (using Laravel 4)
... you should be committing your composer.lock file and doing a composer install on a production environment which is less resource intensive.
More details here:
https://github.com/composer/composer/issues/1898#issuecomment-23453850
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jquery find closest previous sibling with class
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Try:
$('li.current_sub').prevAll("li.par_cat:first");
Tested it with your markup:
$('li.current_sub').prevAll("li.par_cat:first").text("woohoo");
will fill up the closest previous li.par_cat with "woohoo".
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Python argparse: How to insert newline in the help text?
...nfortunately Only the name of this class is considered a public API. All the methods provided by the class are considered an implementation detail. So probably not a great idea, although it might not matter, since 2.7 is meant to be the last 2.x python and you'll be expected to refactor lots ...
Why does GitHub recommend HTTPS over SSH?
...on the widest range of networks and platforms, and by users who are new to all this.
There is no inherent flaw in SSH (if there was they would disable it) -- in the links below, you will see that they still provide details about SSH connections too:
HTTPS is less likely to be blocked by a firewal...
When should we use Observer and Observable?
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In very simple terms (because the other answers are referring you to all the official design patterns anyway, so look at them for further details):
If you want to have a class which is monitored by other classes in the ecosystem of your program you say that you want the class to be observable...
Best practice to run Linux service as a different user
...ervices default to starting as root at boot time on my RHEL box. If I recall correctly, the same is true for other Linux distros which use the init scripts in /etc/init.d .
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Good tutorial for using HTML5 History API (Pushstate?) [closed]
...great tutorial the Mozilla Developer Network page on this functionality is all you'll need: https://developer.mozilla.org/en/DOM/Manipulating_the_browser_history
Unfortunately, the HTML5 History API is implemented differently in all the HTML5 browsers (making it inconsistent and buggy) and has no f...