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What is the difference between pluck and collect in Rails?
...er.first.gifts.collect(&:id)
You have objects with all fields loaded and you simply get the id thanks to the method based on Enumerable.
So:
if you only need the id with Rails 4, use ids: User.first.gifts.ids
if you only need some fields with Rails 4, use pluck: User.first.gifts.pluck(:id, ...
Eclipse Android and gitignore
...itHub, it also includes amongst other things the .project, I disagree here and want your opinion. Scenario: I added new classes to my project. When I pulled from another machine, they were not in the project. Please check it out: github.com/github/gitignore/blob/master/Global/…
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Java default constructor
...or — can you tell me which one of the following is a default constructor and what differentiates it from any other constructor?
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if else statement in AngularJS templates
...ch a video list from the Youtube API. Some of the videos are in 16:9 ratio and some are in 4:3 ratio.
10 Answers
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Is there a float input type in HTML5?
...g to html5.org , the "number" input type's "value attribute, if specified and not empty, must have a value that is a valid floating point number."
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Revert to a commit by a SHA hash in Git? [duplicate]
...eate the correct state of the index to make the commit.
# Reset the index and working tree to the desired tree
# Ensure you have no uncommitted changes that you want to keep
git reset --hard 56e05fced
# Move the branch pointer back to the previous HEAD
git reset --soft HEAD@{1}
git commit -m "Rev...
Opening port 80 EC2 Amazon web services [closed]
...to the "Network & Security" -> Security Group settings in the left hand navigation
Find the Security Group that your instance is apart of
Click on Inbound Rules
Use the drop down and add HTTP (port 80)
Click Apply and enjoy
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Why can't I center with margin: 0 auto?
I have a #header div that is 100% width and within that div I have an unordered list. I have applied margin: 0 auto to the unordered list but it won't center it within the header div.
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sqlalchemy flush() and get inserted id?
...re populated immediately within the flush() process as they are generated, and no call to commit() should be required. So the answer here lies in one or more of the following:
The details of your mapping
If there are any odd quirks of the backend in use (such as, SQLite doesn't generate integer v...
How can you programmatically tell an HTML SELECT to drop down (for example, due to mouseover)?
...ou can't do this with a HTML select tag, but you can do it with JavaScript and HTML. There are variety of existing controls that do this - for instance, the "suggest" list attached to the SO "interesting/ignored tag" entry, or Gmail's lookup for email adresses.
There are many JavaScript+HTML contro...