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How can I see the SQL that will be generated by a given ActiveRecord query in Ruby on Rails

...eir queries directly. It is private API so there is a huge risk that Rails 3 will totally break it, but for debugging, it is an ok solution. The method is construct_finder_sql(options) (lib/active_record/base.rb:1681) you will have to use send because it is private. Edit: construct_finder_sql was...
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Flatten an irregular list of lists

... 390 Using generator functions can make your example a little easier to read and probably boost the...
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Rails: Is there a rails trick to adding commas to large numbers?

... 354 You want the number_with_delimiter method. For example: <%= number_with_delimiter(@number,...
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Pandas count(distinct) equivalent

...ple: In [2]: table Out[2]: CLIENTCODE YEARMONTH 0 1 201301 1 1 201301 2 2 201301 3 1 201302 4 2 201302 5 2 201302 6 3 201302 In [3]: table.groupby('YEARMONTH').CLIENTCODE.nunique() Out[3]: YEARM...
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Why did Rails4 drop support for “assets” group in the Gemfile

In Rails 3, gems used exclusively to generate assets in the asset pipeline were properly placed in the assets group of the Gemfile: ...
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Can I have multiple :before pseudo-elements for the same element?

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Which UUID version to use?

...eed to always generate the same UUID from a given name, you want a version 3 or version 5. Version 3: This generates a unique ID from an MD5 hash of a namespace and name. If you need backwards compatibility (with another system that generates UUIDs from names), use this. Version 5: This generates ...
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Pairwise crossproduct in Python [duplicate]

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Python - Count elements in list [duplicate]

... 399 len() >>> someList=[] >>> print len(someList) 0 ...
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Convert all strings in a list to int

...the map function (in Python 2.x): results = map(int, results) In Python 3, you will need to convert the result from map to a list: results = list(map(int, results)) share | improve this answer ...