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How do I check if a column is empty or null in MySQL?
...e_col = ' ' (one space inserted in the string) then it works on both MySQL and Oracle, see answer of "onedaywhen". some_col = '' doesn't work on Oracle as empty strings mean NULL there.
– Johanna
May 18 '15 at 14:07
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How to fix “Headers already sent” error in PHP
...ically
Previous error messages or notices
Intentional:
print, echo and other functions producing output
Raw <html> sections prior <?php code.
Why does it happen?
To understand why headers must be sent before output it's necessary
to look at a typical HTTP
response. PHP scripts ...
Difference between map, applymap and apply methods in Pandas
...rame’s apply method does exactly this:
In [116]: frame = DataFrame(np.random.randn(4, 3), columns=list('bde'), index=['Utah', 'Ohio', 'Texas', 'Oregon'])
In [117]: frame
Out[117]:
b d e
Utah -0.029638 1.081563 1.280300
Ohio 0.647747 0.831136 -1.549481
Tex...
Any good boolean expression simplifiers out there? [closed]
I was refactoring old code and encountered several IF conditions that were way too complex and long and I'm certain they can be simplified. My guess is that those conditions grew so much because of later modifications.
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Where should @Service annotation be kept? Interface or Implementation?
...g Spring. I'm required to use the @Service annotation. I have ServiceI and ServiceImpl such that ServiceImpl implements ServiceI . I'm confused here as to where should I keep the @Service annotation.
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Finding local IP addresses using Python's stdlib
... addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?
45 Answers
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What is the role of the bias in neural networks? [closed]
I'm aware of the gradient descent and the back-propagation algorithm. What I don't get is: when is using a bias important and how do you use it?
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What exactly are iterator, iterable, and iteration?
What is the most basic definition of "iterable", "iterator" and "iteration" in Python?
13 Answers
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Is gcc's __attribute__((packed)) / #pragma pack unsafe?
...6 systems won't reveal the problem. (On the x86, misaligned accesses are handled in hardware; if you dereference an int* pointer that points to an odd address, it will be a little slower than if it were properly aligned, but you'll get the correct result.)
On some other systems, such as SPARC, att...
How can I capitalize the first letter of each word in a string?
...ition works in many contexts but it means that apostrophes in contractions and possessives form word boundaries, which may not be the desired result:
>>> "they're bill's friends from the UK".title()
"They'Re Bill'S Friends From The Uk"
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