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Best way to check for “empty or null value”
...y string equals any string of spaces when cast to char(n):
SELECT ''::char(5) = ''::char(5) AS eq1
, ''::char(5) = ' '::char(5) AS eq2
, ''::char(5) = ' '::char(5) AS eq3;
Result:
eq1 | eq2 | eq3
----+-----+----
t | t | t
Test for "null or empty string" with char(n):
SEL...
Maven in Eclipse: step by step installation [closed]
I have spent been on the Maven site reading the 5- and 30-minute tutorials, and trialing Maven out for the first time.
13 A...
Canvas width and height in HTML5
Is it possible to fix the width and height of an HTML5 canvas element?
4 Answers
4
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Difference between reduce and foldLeft/fold in functional programming (particularly Scala and Scala
...tInt()).par
scala> timeMany(1000, intParList.reduce(_ + _))
Took 462.395867 milli seconds
scala> timeMany(1000, intParList.foldLeft(0)(_ + _))
Took 2589.363031 milli seconds
reduce vs fold
Now this is where it gets a little closer to the FP / mathematical roots, and a little trickier to e...
read complete file without using loop in java
...
5 Answers
5
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Setting PATH environment variable in OSX permanently
...
NitishNitish
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How to configure Ruby on Rails with no database?
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54
Uncomment this line in the environment.rb file:
config.frameworks -= [ :active_record, :active...
What is the difference between std::array and std::vector? When do you use one over other? [duplicat
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159
std::array is just a class version of the classic C array. That means its size is fixed at com...
Python assigning multiple variables to same value? list behavior
... are naming the same object, use the is operator:
>>> a=b=c=[0,3,5]
>>> a is b
True
You then ask:
what is different from this?
d=e=f=3
e=4
print('f:',f)
print('e:',e)
Here, you're rebinding the name e to the value 4. That doesn't affect the names d and f in any way.
I...
My Understanding of HTTP Polling, Long Polling, HTTP Streaming and WebSockets
... leggetter
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answered Sep 23 '12 at 20:57
kanakakanaka
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