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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
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1003
I would recommend using INSERT...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the ro...
What's the difference between a proc and a lambda in Ruby?
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An example:
p = Proc.new {|a, b| puts a**2+b**2 } # => #<Proc:0x3c7d28@(irb):1>
p.call 1, 2 # => 5
p.call 1 # => NoMethodError: undefined method `**' for nil:NilClass
p.call 1, 2, 3 # => 5
l = lambda {|a, b| puts a**2+b**2 } # => #<Proc:0x15016c@(irb):5 (lambda)>
l.ca...
Skipping Iterations in Python
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398
You are looking for continue.
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Django removing object from ManyToMany relationship
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3 Answers
3
Active
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Python set to list
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Your code does work (tested with cpython 2.4, 2.5, 2.6, 2.7, 3.1 and 3.2):
>>> a = set(["Blah", "Hello"])
>>> a = list(a) # You probably wrote a = list(a()) here or list = set() above
>>> a
['Blah', 'Hello']
Check that you didn't overwrite list by accident...
Resize image proportionally with MaxHeight and MaxWidth constraints
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3 Answers
3
Active
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Pythonic way to create a long multi-line string
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2313
Are you talking about multi-line strings? Easy, use triple quotes to start and end them.
s = ...
Select every Nth element in CSS
...;/h1>
<div>1</div> <div>2</div>
<div>3</div> <div>4</div>
<h2></h2>
<div>5</div> <div>6</div>
<div>7</div> <div>8</div>
<h2></h2>
<div>9</div> <...
What exactly is Java EE?
... maintain. Spring was then a much better alternative to EJB2. But since EJB3 (Java EE 5), the EJB API was much improved based on lessons learnt from Spring. Since CDI (Java EE 6), there's not really a reason to look at again another framework like Spring to make the developers more easy as to develo...
What is tail recursion?
...ple function that adds the first N natural numbers. (e.g. sum(5) = 1 + 2 + 3 + 4 + 5 = 15).
Here is a simple JavaScript implementation that uses recursion:
function recsum(x) {
if (x === 1) {
return x;
} else {
return x + recsum(x - 1);
}
}
If you called recsum(5), th...