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How to display unique records from a has_many through relationship?
...ct => "DISTINCT products.*). In the first case, ALL records are fetched and rails removes the duplicates for you. In the later case, only non-duplicate records are fetched from the db so it might offer better performance if you have a large result set.
– mbreining
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Clojure: cons (seq) vs. conj (list)
I know that cons returns a seq and conj returns a collection. I also know that conj "adds" the item to the optimal end of the collection, and cons always "adds" the item to the front. This example illustrates both of these points:
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How do I check what version of Python is running my script?
... to your code:
assert sys.version_info >= (2, 5)
This compares major and minor version information. Add micro (=0, 1, etc) and even releaselevel (='alpha','final', etc) to the tuple as you like. Note however, that it is almost always better to "duck" check if a certain feature is there, and if...
How to create CSV Excel file C#? [closed]
...ow can i add two table in single file,means i have a one table of two rows and other table is 10 rows and both have unique column name.I want to add two rows table on top and after gap of two lines i want to add second table.
– Floki
Jun 17 '15 at 12:19
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Why does MSBuild look in C:\ for Microsoft.Cpp.Default.props instead of c:\Program Files (x86)\MSBui
...I got this problem when publishing a cocos2d-x application using their command line tool, which calls MSBuild. I'm using Win 7 64-bit, VS2013 express, cocos2d-x version 3.3, .NET Framework 4.5 installed.
I fixed the problem by setting the following before running the cocos.py publish command:
SET ...
Static function variables in Swift
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Yeah, I continued playing around a bit and this was basically the really clunky solution I came up with as well.
– nhgrif
Aug 18 '14 at 0:29
17
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How can I set a website image that will show as preview on Facebook?
... share a link on facebook it will automatically find images on the website and randomly picks one as a preview. How can you influence the preview image? When a person shares the website link on his facebook?
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Is there a standard keyboard shortcut to build the current project in Visual Studio?
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Assigning the shortcut to "Build.BuildOnlyProject" command doesn't seem to work in VS2008.
Assign the shortcut to "Build.BuildSelection". If you have a solution with several projects and files open from the various projects, whatever file you are currently editing will define ...
Rails: update_attribute vs update_attributes
... send(name.to_s + '=', value)
2616: save(false)
2617: end
and now refer update_attributes and look at its code you get
# File vendor/rails/activerecord/lib/active_record/base.rb, line 2621
2621: def update_attributes(attributes)
2622: self.attributes = attribute...
how to get the last character of a string?
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An elegant and short alternative, is the String.prototype.slice method.
Just by:
str.slice(-1);
A negative start index slices the string from length+index, to length, being index -1, the last character is extracted:
"abc".slice(-1)...