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MySQL SELECT only not null values
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You should use IS NOT NULL. (The comparison operators = and <> both give UNKNOWN with NULL on either side of the expression.)
SELECT *
FROM table
WHERE YourColumn IS NOT NULL;
Just for completeness I'll mention that in MySQL you can also negate the null safe equality op...
#if DEBUG vs. Conditional(“DEBUG”)
Which is better to use, and why, on a large project:
8 Answers
8
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How to pick just one item from a generator?
...__() in py3k. The builtin next(iterator) has been around since Python 2.6, and is what should be used in all new Python code, and it's trivial to backimplement if you need to support py <= 2.5.
– Jonathan Baldwin
Apr 10 '14 at 19:58
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How to save all the variables in the current python session?
...s()[key]
except TypeError:
#
# __builtins__, my_shelf, and imported modules can not be shelved.
#
print('ERROR shelving: {0}'.format(key))
my_shelf.close()
To restore:
my_shelf = shelve.open(filename)
for key in my_shelf:
globals()[key]=my_shelf[key]
my_she...
C++ include and import difference
What is the difference between #include and #import in C++?
5 Answers
5
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How to parse a string into a nullable int
...eturn null;
}
Edit @Glenn int.TryParse is "built into the framework". It and int.Parse are the way to parse strings to ints.
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How can I create download link in HTML?
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@Dudeson please specify what "won't work" and which version(s) of IE you are talking about. (It is now safe to use the approach described TIIUNDER's much more recent answer below, though. It should get the accept mark.)
– Pekka
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New self vs. new static
I am converting a PHP 5.3 library to work on PHP 5.2. The main thing standing in my way is the use of late static binding like return new static($options); , if I convert this to return new self($options) will I get the same results?
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HTML “overlay” which allows clicks to fall through to elements behind it [duplicate]
...ng to overlay a element on top of a webpage (to draw arbitrary graphics), and I've come to the point where I can stack it inside of a element on top of everything, but this prevents the user from clicking on any links/buttons/etc.
Is there a way to have its content float on top of everything (it's...
How do I create a ListView with rounded corners in Android?
How do I create a ListView with rounded corners in Android?
11 Answers
11
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