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JPA or JDBC, how are they different?
I am learning Java EE and I downloaded the eclipse with glassfish for the same. I saw some examples and also read the Oracle docs to know all about Java EE 5. Connecting to a database was very simple. I opened a dynamic web project, created a session EJB , I used EntityManager and with the get meth...
Flatten an Array of Arrays in Swift
Is there a counterpart in Swift to flatten in Scala, Xtend, Groovy, Ruby and co?
14 Answers
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Was PreferenceFragment intentionally excluded from the compatibility package?
I'm looking to write preferences that can be applied to both 3.0 and pre-3.0 devices. Discovering that PreferenceActivity contains deprecated methods (although these are used in the accompanying sample code), I looked at PreferenceFragement and the compatibility package to solve my woes.
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Rails: FATAL - Peer authentication failed for user (PG::Error)
I am running my development on Ubuntu 11.10, and RubyMine
8 Answers
8
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Python Sets vs Lists
...cture is more efficient/speedy? Assuming that order is not important to me and I would be checking for duplicates anyway, is a Python set slower than a Python list?
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How to remove a key from a Python dictionary?
...y', None)
This will return my_dict[key] if key exists in the dictionary, and None otherwise. If the second parameter is not specified (ie. my_dict.pop('key')) and key does not exist, a KeyError is raised.
To delete a key that is guaranteed to exist, you can also use
del my_dict['key']
This wil...
Effective way to find any file's Encoding
Yes is a most frequent question, and this matter is vague for me and since I don't know much about it.
9 Answers
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BigDecimal setScale and round
...lluded to but not directly addressed is the difference between "precision" and "scale" and how they are used in the two statements. "precision" is the total number of significant digits in a number. "scale" is the number of digits to the right of the decimal point.
The MathContext constructor onl...
How to pass command line arguments to a rake task
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Options and dependencies need to be inside arrays:
namespace :thing do
desc "it does a thing"
task :work, [:option, :foo, :bar] do |task, args|
puts "work", args
end
task :another, [:option, :foo, :bar] do |task, args|...
jQuery set checkbox checked
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Taking all of the proposed answers and applying them to my situation - trying to check or uncheck a checkbox based on a retrieved value of true (should check the box) or false (should not check the box) - I tried all of the above and found that using .prop("ch...