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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...
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...
Should the folders in a solution match the namespace?
...fit in my opinion of using multiple namespaces in large projects is having extra organization when viewing classes in any tooling that displays classes in a namespaces hierarchy. Even documentation. Obviously having just one namespace in the project results in all classes being displayed in a single...
How to determine if an NSDate is today?
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Clever idea. But I assume that looking for the string "Today" would break if you localize.
– Basil Bourque
Dec 15 '12 at 3:50
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Is an entity body allowed for an HTTP DELETE request?
...ompletely identify the resource to delete. However, is it allowable to add extra meta-data as part of the entity body of the request?
...
Why is my xlabel cut off in my matplotlib plot?
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I find it pretty weird that one would need to make an extra call to make room for an essential part of a plot. What's the reasoning behind this?
– a different ben
Apr 9 '12 at 8:09
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Elasticsearch query to return all records
I have a small database in Elasticsearch and for testing purposes would like to pull all records back. I am attempting to use a URL of the form...
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How to implement __iter__(self) for a container object (Python)
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I normally would use a generator function. Each time you use a yield statement, it will add an item to the sequence.
The following will create an iterator that yields five, and then every item in some_list.
def __iter__(self):
...
Merge up to a specific commit
... work and want to merge newbranch to master ; however, I have made some extra changes to newbranch and I want to merge newbranch up to the fourth-from-the-last commit to master .
...