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How do I perform the SQL Join equivalent in MongoDB?
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Of course Mongo is not a relational database, and the devs are being careful to recommend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
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Logging in Scala
...hat is consistent with the language philosophy, does not clutter the code, and is low-maintenance and unobtrusive. Here's a basic requirement list:
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How to remove element from an array in JavaScript?
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And the follow-on question: arr.splice(1,1) for the second element.
– slebetman
Jan 5 '10 at 2:42
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A simple scenario using wait() and notify() in java
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The wait() and notify() methods are designed to provide a mechanism to allow a thread to block until a specific condition is met. For this I assume you're wanting to write a blocking queue implementation, where you have some fixed size ...
Upgrade python in a virtualenv
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Did you see this? If I haven't misunderstand that answer, you may try to create a new virtualenv on top of the old one. You just need to know which python is going to use your virtualenv (you will need to see your virtualenv version).
If your virtualenv is install...
boost::flat_map and its performance compared to map and unordered_map
...haven't been able to find any performance comparisons. How does it compare and what are the best use cases for it?
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Setting Short Value Java
... There are suffixes for other types as well: d/D makes a double and f/F makes a float!
– Joachim Sauer
Feb 19 '10 at 8:48
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How do DATETIME values work in SQLite?
I’m creating Android apps and need to save date/time of the creation record. The SQLite docs say, however, "SQLite does not have a storage class set aside for storing dates and/or times" and it's "capable of storing dates and times as TEXT, REAL, or INTEGER values".
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Checkboxes in web pages – how to make them bigger?
The standard checkboxes rendered in most browsers are quite small and don’t increase in size even when a larger font is used. What is the best, browser-independent way to display larger checkboxes?
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Numpy first occurrence of value greater than existing value
I have a 1D array in numpy and I want to find the position of the index where a value exceeds the value in numpy array.
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