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What is the difference between pluck and collect in Rails?
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When you do:
User.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...
How do I query for all dates greater than a certain date in SQL Server?
...o a proper datetime, and using single quotes will fix this issue.)
Technically, the parser might allow you to get away with
select *
from dbo.March2010 A
where A.Date >= '2010-04-01'
it will do the conversion for you, but in my opinion it is less readable than explicitly converting to a Da...
How to find memory leak in a C++ code/project?
...e software tools
1
Understand the operator basics. The C++ operator new allocates heap memory. The delete operator frees heap memory. For every new, you should use a delete so that you free the same memory you allocated:
char* str = new char [30]; // Allocate 30 bytes to house a string.
delete ...
Flexbox not giving equal width to elements
...t has up to 5 items and as little as 3, but it's not dividing the width equally between all the elements.
2 Answers
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Are default enum values in C the same for all compilers?
When declaring an enum as shown below, do all C compilers set the default values as x=0 , y=1 , and z=2 on both Linux and Windows systems?
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What is a Python equivalent of PHP's var_dump()? [duplicate]
...lay a value nicely, you can use the pprint module. The easiest way to dump all variables with it is to do
from pprint import pprint
pprint(globals())
pprint(locals())
If you are running in CGI, a useful debugging feature is the cgitb module, which displays the value of local variables as part of...
Add and remove multiple classes in jQuery
...eClass() only and no need to write any class name in removeClass to remove all the added classes and add any class by choice. Yes its working...!
– Raman
Aug 25 '11 at 6:49
3
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Guid.NewGuid() vs. new Guid()
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new Guid() makes an "empty" all-0 guid (00000000-0000-0000-0000-000000000000 is not very useful).
Guid.NewGuid() makes an actual guid with a unique value, what you probably want.
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XML Document to String
... String representation of a XML Document ( org.w3c.dom.Document )? That is all nodes will be on a single line.
3 Answers
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How to compile without warnings being treated as errors?
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You can make all warnings being treated as such using -Wno-error. You can make specific warnings being treated as such by using -Wno-error=<warning name> where <warning name> is the name of the warning you don't want treated a...