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What is the difference between Gemfile and Gemfile.lock in Ruby on Rails
I am a beginner to Ruby on Rails and I am using Rails 3.0.9.
3 Answers
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How do SQL EXISTS statements work?
I'm trying to learn SQL and am having a hard time understanding EXISTS statements. I came across this quote about "exists" and don't understand something:
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What is the difference between an expression and a statement in Python?
In Python, what is the difference between expressions and statements?
14 Answers
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Listing each branch and its last revision's date in Git
I need to delete old and unmaintained branches from our remote repository. I'm trying to find a way with which to list the remote branches by their last modified date, and I can't.
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Store boolean value in SQLite
...an storage class. Instead, Boolean values are stored as integers 0 (false) and 1 (true).
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Why does typeof NaN return 'number'?
...eration
which return NaN:
Operations with a NaN as at least one operand
Indeterminate forms
The divisions 0/0, ∞/∞, ∞/−∞, −∞/∞, and −∞/−∞
The multiplications 0×∞ and 0×−∞
The power 1^∞
The additions ∞ + (−∞), (−∞) + ∞ and e...
How to use R's ellipsis feature when writing your own function?
...nts. For example, the function data.frame takes any number of arguments, and each argument becomes the data for a column in the resulting data table. Example usage:
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What's the difference between --general-numeric-sort and --numeric-sort options in gnu sort
...mbers as floats, this allows scientific notation eg 1.234E10 but is slower and subject to rounding error (1.2345678 could come after 1.2345679), numeric sort is just a regular alphabetic sort that knows 10 comes after 9.
See http://www.gnu.org/software/coreutils/manual/html_node/sort-invocatio...
Schema for a multilanguage database
...es, localizability is not an issue. We can use language specific resources and have all kinds of tools that work well with them.
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Hibernate, @SequenceGenerator and allocationSize
...nce by one , multiple this value by 50 (default allocationSize value) - and then uses this value as entity ID.
6 Answers...