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mongodb count num of distinct values per field/key
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MongoDB has a distinct command which returns an array of distinct values for a field; you can check the length of the array for a count.
There is a shell db.collection.distinct() helper as well:
> db.countries.distinct('country');
[ "Spain", "Engl...
How to make jQuery to not round value returned by .width()?
I've searched around and couldn't find this. I'm trying to get the width of a div, but if it has a decimal point it rounds the number.
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How to execute PHP code from the command line?
...function_exists("my_func")) echo 'function exists'; directly with the command line without having to use a seperate php file.
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WebSockets vs. Server-Sent events/EventSource
Both WebSockets and Server-Sent Events are capable of pushing data to browsers. To me they seem to be competing technologies. What is the difference between them? When would you choose one over the other?
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How to give System property to my test via Gradle and -D
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The -P flag is for gradle properties, and the -D flag is for JVM properties. Because the test may be forked in a new JVM, the -D argument passed to gradle will not be propagated to the test - it sounds like that is the behavior you are seeing.
You can use the sy...
Why do you need to create a cursor when querying a sqlite database?
I'm completely new to Python's sqlite3 module (and SQL in general for that matter), and this just completely stumps me. The abundant lack of descriptions of cursor objects (rather, their necessity) also seems odd.
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Linq to SQL how to do “where [column] in (list of values)”
I have a function where I get a list of ids, and I need to return the a list matching a description that is associated with the id. E.g.:
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Can you do this HTML layout without using tables?
...wrong with using the tools that are available to you to do the job quickly and correctly.
In this case a table worked perfectly.
I personally would have used a table for this.
I think nested tables should be avoided, things can get messy.
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Does async(launch::async) in C++11 make thread pools obsolete for avoiding expensive thread creation
...rong. I was under the impression that Linux thread creation was very cheap and after testing I determined that the overhead of function call in a new thread vs. a normal one is enormous. The overhead for creating a thread to handle a function call is something like 10000 or more times slower than a ...
Get current batchfile directory
Firstly, I saw this topic but I couldn't understand that.
4 Answers
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