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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, ...
IF statement: how to leave cell blank if condition is false (“” does not work)
...ce.
See this post for a few other options.
edit
To reflect the comments and what you ended up doing: Instead of evaluating to "" enter another value such as 'deleteme' and then search for 'deleteme' instead of blanks.
=IF(ISBLANK(C1),TRUE,(TRIM(C1)="deleteme"))
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Swift - Split string over multiple lines
...he expression is "too complex to be solved in a reasonable amount of time" and to consider breaking it down to simpler expressions. That's ugly but easy enough to accomplish, just wrap sections in parens.
– clearlight
Dec 7 '14 at 0:02
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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...
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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How to determine equality for two JavaScript objects?
...ortant to determine whether any two instances of MyClass are equal, only a and b are important. In some cases c might vary between instances and yet not be significant during comparison.
Note this issue applies when members may themselves also be instances of a type and these each would all be req...
Google Maps API v3: How to remove all markers?
... The markers are still kept in the array though so it will grow larger and larger. Would suggest clearing the array as well after the loop
– Ami
Oct 5 '12 at 9:08
5
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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...
Regex to match string containing two names in any order
I need logical AND in regex.
8 Answers
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