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Ruby on Rails Callback, what is difference between :before_save and :before_create?
Could you explain in detail what the :before_save and :before_create Ruby on Rails callbacks are, and what they have to do with Rails validations? Does validation occur after :before_save or :before_create ?
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How do I hide the status bar in a Swift iOS app?
...ould implement prefersStatusBarHidden on your view controller(s):
Swift 3 and later
override var prefersStatusBarHidden: Bool {
return true
}
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Static methods in Python?
...should only be used if you have to support ancient versions of Python (2.2 and 2.3)
class MyClass(object):
def the_static_method(x):
print(x)
the_static_method = staticmethod(the_static_method)
MyClass.the_static_method(2) # outputs 2
This is entirely identical to the first exampl...
SQL Case Sensitive String Compare
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Yes, the Standard approach is to use a case-insensitive collation, though the collations themselves are vendor-specific. Is yours SQL Server syntax?
– onedaywhen
Oct 20 '10 at 9:24
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unsigned APK can not be installed
...people for testing.
I have installed it on my Desire directly from eclipse and it works fine.
7 Answers
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MySQL load NULL values from CSV data
...is will do what you want. It reads the fourth field into a local variable, and then sets the actual field value to NULL, if the local variable ends up containing an empty string:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(one, two, three, ...
In git, what is the difference between merge --squash and rebase?
I'm new to git and I'm trying to understand the difference between a squash and a rebase. As I understand it you perform a squash when doing a rebase.
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What is the apply function in Scala?
I never understood it from the contrived unmarshalling and verbing nouns ( an AddTwo class has an apply that adds two!) examples.
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Django - what is the difference between render(), render_to_response() and direct_to_template()?
Whats the difference (in language a python/django noob can understand) in a view between render() , render_to_response() and direct_to_template() ?
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Using the star sign in grep
...ou need to tell it what you repeat. /*abc*/ matches a string containing ab and zero or more c's (because the second * is on the c; the first is meaningless because there's nothing for it to repeat). If you want to match anything, you need to say .* -- the dot means any character (within certain guid...