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What's the $unwind operator in MongoDB?
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First off, welcome to MongoDB!
The thing to remember is that MongoDB employs an "NoSQL" approach to data storage, so perish the thoughts of selects, joins, etc. from your mind. The way that it stores your data is in the form of documents and collections, which a...
Importing CommonCrypto in a Swift framework
How do you import CommonCrypto in a Swift framework for iOS?
16 Answers
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Odd behavior when Java converts int to byte?
Mindboggling. Why is the output -124 ?
11 Answers
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quick random row selection in Postgres
I have a table in postgres that contains couple of millions of rows. I have checked on the internet and I found the following
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How to use index in select statement?
Lets say in the employee table, I have created an index(idx_name) on the emp_name column of the table.
8 Answers
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Creating a new dictionary in Python
I want to build a dictionary in Python. However, all the examples that I see are instantiating a dictionary from a list, etc . ..
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How to know if other threads have finished?
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There are a number of ways you can do this:
Use Thread.join() in your main thread to wait in a blocking fashion for each Thread to complete, or
Check Thread.isAlive() in a polling fashion -- generally discouraged -- to wait until each Thread has completed, or
Unorthodox, for each T...
How to join two JavaScript Objects, without using JQUERY [duplicate]
I have two json objects obj1 and obj2, i want to merge them and crete a single json object.
The resultant json should have all the values from obj2 and the values from obj1 which is not present in obj2.
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How to overcome TypeError: unhashable type: 'list'
I'm trying to take a file that looks like this:
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TypeScript “this” scoping issue when called in jquery callback
I'm not sure of the best approach for handling scoping of "this" in TypeScript.
4 Answers
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