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Paperclip::Errors::MissingRequiredValidatorError with Rails 4
...line to your Post model, after specifying has_attached_file :image
Option 1: Validate content type
validates_attachment_content_type :image, :content_type => ["image/jpg", "image/jpeg", "image/png", "image/gif"]
-OR- another way
validates_attachment :image, content_type: { content_type: ["im...
R programming: How do I get Euler's number?
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150
The R expression
exp(1)
represents e, and
exp(2)
represents e^2.
This works because exp...
Show current state of Jenkins build on GitHub repo
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12 Answers
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Active
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SQL Query to concatenate column values from multiple rows in Oracle
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10 Answers
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Active
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Is it fine to have foreign key as primary key?
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134
Foreign keys are almost always "Allow Duplicates," which would make them unsuitable as Primary...
what is faster: in_array or isset? [closed]
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119
The answers so far are spot-on. Using isset in this case is faster because
It uses an O(1) h...
What is a 'semantic predicate' in ANTLR?
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ANTLR 4
For predicates in ANTLR 4, checkout these stackoverflow Q&A's:
Syntax of semant...
Rebasing remote branches in Git
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186
It comes down to whether the feature is used by one person or if others are working off of it....
Running multiple commands in one line in shell
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edited Apr 26 '14 at 1:06
answered Feb 27 '11 at 1:44
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How to get a complete list of ticker symbols from Yahoo Finance? [closed]
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There is a nice C# wrapper for the Yahoo.Finance API at http://code.google.com/p/yahoo-finance-...