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Get the latest record from mongodb collection
...1 means order opposite of the one that records are inserted in.
Edit: For all the downvoters, above is a Mongoose syntax,
mongo CLI syntax is: db.collectionName.find({}).sort({$natural:-1}).limit(1)
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How do I compare two hashes?
...=> [["c", 3]]
Hash[*difference.flatten]
=> {"c"=>3}
Doing it all in one operation and getting rid of the difference variable:
Hash[*(
(hash3.size > hash1.size) \
? hash3.to_a - hash1.to_a \
: hash1.to_a - hash3.to_a
).flatten]
=> {"c"=>3}
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Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = ...
Finding all cycles in a directed graph
How can I find (iterate over) ALL the cycles in a directed graph from/to a given node?
17 Answers
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unique object identifier in javascript
...niqueId());
Take care to make sure that whatever member you use to internally store the unique ID doesn't collide with another automatically created member name.
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Can someone explain the traverse function in Haskell?
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traverse is the same as fmap, except that it also allows you to run effects while you're rebuilding the data structure.
Take a look at the example from the Data.Traversable documentation.
data Tree a = Empty | Leaf a | Node (Tree a) a (Tree a)
The Functor instance of Tr...
How to convert a Title to a URL slug in jQuery?
...on an app in CodeIgniter, and I am trying to make a field on a form dynamically generate the URL slug. What I'd like to do is remove the punctuation, convert it to lowercase, and replace the spaces with hyphens. So for example, Shane's Rib Shack would become shanes-rib-shack.
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Python requests - print entire http request (raw)?
...ests.post(...) (or requests.get or requests.put, etc) methods, you can actually get the PreparedResponse through response.request. It can save the work of manually manipulating requests.Request and requests.Session, if you don't need to access the raw http data before you receive a response.
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Why does HTML5 form-validation allow emails without a dot?
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I wonder when the last time someone actually sent an email to localhost!
– Matthew Lock
May 19 '17 at 3:14
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Preserving order with LINQ
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Actually, I think Distinct preserves original (first found) order - so {1,2,1,3,1,3,4,1,5} would be {1,2,3,4,5}
– Marc Gravell♦
Oct 15 '08 at 14:33
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