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How do I perform the SQL Join equivalent in MongoDB?
...rect. The new $lookup operator added to the aggregation pipeline is essentially identical to a left outer join:
https://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <...
Relational table naming convention [closed]
...e theory.
Some of the wonderful things about Standards are:
they are all integrated with each other
they work together
they were written by minds greater than ours, so we do not have to
debate them.
The standard table name refers to each row in the table, which is used in the all verbiage, n...
How do I avoid capturing self in blocks when implementing an API?
...ied inside the block (we're not doing that) but also they are not automatically retained when the block is retained (unless you are using ARC). If you do this, you must be sure that nothing else is going to try to execute the block after the MyDataProcessor instance is released. (Given the structure...
How to change value of object which is inside an array using JavaScript or jQuery?
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@FrederikoCesar not in all cases, iterating over each object costs more than slicing the array and inject the new object using spread operator
– Maged Mohamed
Feb 29 at 21:33
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Define a lambda expression that raises an Exception
...ur goal is to avoid a def, this obviously doesn't cut it. It does, however allow you to conditionally raise exceptions, e.g.:
y = lambda x: 2*x if x < 10 else raise_(Exception('foobar'))
Alternatively you can raise an exception without defining a named function. All you need is a strong stom...
Dynamically set local variable [duplicate]
How do you dynamically set local variable in Python (where the variable name is dynamic)?
7 Answers
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Does “\d” in regex mean a digit?
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@FarazAhmad, probably not, you have to specify all characters separately
– Kirill Polishchuk
Dec 28 '17 at 23:26
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Evenly distributing n points on a sphere
...ating an array N points and node[k] is the kth (from 0 to N-1). If that is all that is confusing you, hopefully you can use that now.
(in other words, k is an array of size N that is defined before the code fragment starts, and which contains a list of the points).
Alternatively, building on the o...
Python Graph Library [closed]
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I just evaluated both. networkx is installable via pip, whereas igraph is not. This makes igraph harder to use as dependencies in your setup.py files.
– exhuma
Aug 10 '12 at 7:46
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Converting an int to std::string
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So you didn't mean it to be compilable, but actually with the include it is :)
– TechNyquist
Jul 19 '16 at 16:54
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