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Extract filename and extension in Bash
...ng with file names without extension: extension=$([[ "$filename" = *.* ]] && echo ".${filename##*.}" || echo ''). Note that if an extension is present, it will be returned including the initial ., e.g., .txt.
– mklement0
Sep 7 '12 at 14:41
...
Rails: select unique values from a column
...ey are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (most efficient)
Model.uniq.pluck(:rating)
# rails 5+
Model.distinct.pluck(:rating)
Update
Apparently, as of rails 5.0.0.1, it works only on "top level" queries, like above. Doesn't work on co...
Getting the SQL from a Django QuerySet [duplicate]
...t the queryset's query attribute.
>>> queryset = MyModel.objects.all()
>>> print(queryset.query)
SELECT "myapp_mymodel"."id", ... FROM "myapp_mymodel"
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Error :Request header field Content-Type is not allowed by Access-Control-Allow-Headers
... extra header. Try prepending the following to your file if you are using PHP:
header("Access-Control-Allow-Origin: *");
header("Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept");
Make sure that you haven't already used header in another file, or you will get a nasty...
How to check if smtp is working from commandline (Linux) [closed]
I have a SMTP-server, for the purpose of this question lets call it: smtp.mydomain.com.
4 Answers
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Omitting all xsi and xsd namespaces when serializing an object in .NET?
...
Also, this doesn't remove all xml namespaces, as the question asked. It removes only the xsi and xsd namespaces, as mentioned in the question stackoverflow.com/questions/258960, which is also cited in this question.
– Cheeso
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How to extract URL parameters from a URL with Ruby or Rails?
...gi/rdoc/classes/CGI.html#M000075
require 'cgi'
CGI::parse('param1=value1&param2=value2&param3=value3')
returns
{"param1"=>["value1"], "param2"=>["value2"], "param3"=>["value3"]}
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Strangest language feature
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Or, more usefully, "0123456789abcdef"[x & 0xf]
– Dipstick
Jan 3 '10 at 15:33
17
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sqlalchemy: how to join several tables by one query?
...rmissions.document,
).filter(
User.email == 'someemail',
).all()
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if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...