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MySQL CONCAT returns NULL if any field contain NULL
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answered Apr 1 '13 at 10:01
John WooJohn Woo
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error: Libtool library used but 'LIBTOOL' is undefined
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143
A good answer for me was to install libtool:
sudo apt-get install libtool
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How do you use window.postMessage across domains?
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3 Answers
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Using bitwise OR 0 to floor a number
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163
How does it work? Our theory was that using such an operator casts the
number to an integer...
How to count TRUE values in a logical vector
...m(z) # gives you NA
table(z)["TRUE"] # gives you 1
length(z[z == TRUE]) # f3lix answer, gives you 2 (because NA indexing returns values)
So I think the safest is to use na.rm = TRUE:
sum(z, na.rm = TRUE) # best way to count TRUE values
(which gives 1). I think that table solution is less effici...
mysql create user if not exists
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answered May 16 '13 at 16:24
AschererAscherer
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How to interactively (visually) resolve conflicts in SourceTree / git
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Best way to add page specific JavaScript in a Rails 3 app?
Rails 3 has some unobtrusive JavaScript which is pretty cool.
10 Answers
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In Ruby on Rails, how do I format a date with the “th” suffix, as in, “Sun Oct 5th”?
...ize method from 'active_support'.
>> time = Time.new
=> Fri Oct 03 01:24:48 +0100 2008
>> time.strftime("%a %b #{time.day.ordinalize}")
=> "Fri Oct 3rd"
Note, if you are using IRB with Ruby 2.0, you must first run:
require 'active_support/core_ext/integer/inflections'
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