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What is the Oracle equivalent of SQL Server's IsNull() function?
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131
coalesce is supported in both Oracle and SQL Server and serves essentially the same function as...
GROUP_CONCAT ORDER BY
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317
You can use ORDER BY inside the GROUP_CONCAT function in this way:
SELECT li.client_id, grou...
Integer division: How do you produce a double?
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163
double num = 5;
That avoids a cast. But you'll find that the cast conversions are well-define...
Add a default value to a column through a migration
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358
Here's how you should do it:
change_column :users, :admin, :boolean, :default => false
B...
Big-O for Eight Year Olds? [duplicate]
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293
One way of thinking about it is this:
O(N^2) means for every element, you're doing something wi...
Why does Razor _layout.cshtml have a leading underscore in file name?
In the default ASP.NET MVC 3 project, layout & partial cshtml files start with an underscore
5 Answers
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Remove blank attributes from an Object in Javascript
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37 Answers
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Do AJAX requests retain PHP Session info?
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edited Nov 20 '12 at 3:50
answered Mar 24 '09 at 11:10
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Painless way to install a new version of R?
...or Thomas
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answered Oct 20 '10 at 11:16
Joris MeysJoris Meys
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Find the extension of a filename in Ruby
...gt; accepted_formats = [".txt", ".pdf"]
=> [".txt", ".pdf"]
irb(main):003:0> File.extname("example.pdf") # get the extension
=> ".pdf"
irb(main):004:0> accepted_formats.include? File.extname("example.pdf")
=> true
irb(main):005:0> accepted_formats.include? File.extname("example.txt...