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How do I check if a column is empty or null in MySQL?
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19 Answers
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Iterate through every file in one directory
...n them, so you can use Dir::each_child or Dir::children (as suggested by ma11hew28) or do something like this:
Dir.foreach('/path/to/dir') do |filename|
next if filename == '.' or filename == '..'
# Do work on the remaining files & directories
end
Dir::foreach and Dir::entries (as well as...
Eclipse/Java code completion not working
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1270
Try restoring the default options in 'Windows > Preferences > Java > Editor > Con...
Is there a way to recover from an accidental “svn revert”?
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10 Answers
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find() with nil when there are no records
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173
Yes, just do:
Challenge.find_by_id(10)
For Rails 4 and 5:
Challenge.find_by(id: 10)
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Introducing FOREIGN KEY constraint may cause cycles or multiple cascade paths - why?
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16 Answers
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从估值5千万到一无所有 90后的他感觉梦境一场 - 资讯 - 清泛网 - 专注C/C++...
...业，当时只有5个人，做一个宠物交易和服务的项目。
2015年1月，20出头的夏军迎来第一波人生高峰，他创办的爱狗团获得了天使轮投资。按照投资协议，对方出资1000万元，分5次给清，占股20%，项目估值5000万元。当时投资人已...
How to Detect if I'm Compiling Code with a particular Visual Studio version?
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_MSC_VER and possibly _MSC_FULL_VER is what you need. You can also examine visualc.hpp in any r...
Get user info via Google API
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Add this to the scope - https://www.googleapis.com/auth/userinfo.profile
And after authorizat...