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MongoDB Aggregation: How to get total records count?
...sults simultaneously in single query. I can't explain how I felt when I finally achieved it LOL.
$result = $collection->aggregate(array(
array('$match' => $document),
array('$group' => array('_id' => '$book_id', 'date' => array('$max' => '$book_viewed'), 'views' => array('...
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 = ...
How do I use Linq to obtain a unique list of properties from a list of objects?
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323
IEnumerable<int> ids = list.Select(x=>x.ID).Distinct();
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How do I undo the most recent local commits in Git?
I accidentally committed the wrong files to Git , but I haven't pushed the commit to the server yet.
86 Answers
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Copying files from Docker container to host
...ncies on a Continuous Integration (CI) server, so that I don't have to install all the runtimes and libraries on the agents themselves.
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How do I format a string using a dictionary in python-3.x?
...3). In many languages, it is known as splat operator. In JavaScript, it's called spread operator. In python, there is no particular name given to this operator.
– abhisekp
Apr 15 '17 at 12:01
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What does the @ symbol before a variable name mean in C#? [duplicate]
...m.
– Justin Skiles
Jan 29 '14 at 19:32
5
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How do you use bcrypt for hashing passwords in PHP?
...d salts (bcrypt REQUIRES salts) and you can be sure that an attack is virtually unfeasible without either ludicrous amount of funds or hardware.
bcrypt uses the Eksblowfish algorithm to hash passwords. While the encryption phase of Eksblowfish and Blowfish are exactly the same, the key schedule pha...
How to delete the last n commits on Github and locally?
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edited Feb 12 '17 at 23:32
tulians
40944 silver badges2121 bronze badges
answered Aug 2 '16 at 14:53
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How do you specify the Java compiler version in a pom.xml file?
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Generally you don't want to value only the source version (javac -source 1.8 for example) but you want to value both the source and the target version (javac -source 1.8 -target 1.8 for example).
Note that from Java 9, you have a ...