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mongodb group values by multiple fields
... $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.
db.books.aggregate(...
What should my Objective-C singleton look like? [closed]
My singleton accessor method is usually some variant of:
26 Answers
26
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What’s the best way to check if a file exists in C++? (cross platform)
...his using standard c++ libs? Preferably without trying to open the file at all.
10 Answers
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UTF-8: General? Bin? Unicode?
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This doesn't really answer the question in depth though. What is the difference between these collations exactly?
– Pekka
Apr 2 '11 at 22:34
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Can I find events bound on an element with jQuery?
...ng, sorry :) $._data(element[0], ‘events’);
– totallyNotLizards
Oct 23 '12 at 8:10
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Dealing with commas in a CSV file
...any easily-available csv library - that is to say RFC 4180.
There's actually a spec for CSV format and how to handle commas:
Fields containing line breaks (CRLF), double quotes, and commas should be enclosed in double-quotes.
http://tools.ietf.org/html/rfc4180
So, to have values foo and ...
Play a Sound with Python [duplicate]
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Avoid oss, it's old. I don't think I even have it installed anymore.
– Jeffrey Aylesworth
Jan 30 '10 at 19:47
8
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What Automatic Resource Management alternatives exist for Scala?
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For now Scala 2.13 has finally supported: try with resources by using Using :), Example:
val lines: Try[Seq[String]] =
Using(new BufferedReader(new FileReader("file.txt"))) { reader =>
Iterator.unfold(())(_ => Option(reader.readLine()).ma...
How do you validate a URL with a regular expression in Python?
...he result of parsing gives you a netloc or path you don't like, you could call that "invalid".
– S.Lott
Jun 29 '09 at 20:44
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How do I get a list of column names from a psycopg2 cursor?
... to generate column labels directly from the selected column names, and recall seeing that python's psycopg2 module supports this feature.
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