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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 = ...
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('...
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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How do I get indices of N maximum values in a NumPy array?
...t been able to find one.
If this solution turns out to be too slow (especially for small n), it may be worth looking at coding something up in Cython.
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Eclipse cannot load SWT libraries
... I get an Unsatisfied Link Error and it will not open. I have recently installed the java JDK and Android SDK, could this be the problem? I followed this tutorial .
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Disable Logback in SpringBoot
...-boot-starter-* dependency is a huge hassle. It seems like Gradle at least allows a global exclusion. This alone is seriously making me consider switching from Maven.
– scottysseus
Apr 26 '19 at 20:46
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How to count total lines changed by a specific author in a Git repository?
...--author="<authorname>" --oneline --shortstat
This gives stats for all commits on the current HEAD. If you want to add up stats in other branches you will have to supply them as arguments to git log.
For passing to a script, removing even the "oneline" format can be done with an empty log f...
Interfaces — What's the point?
...ntract. A set of public methods any implementing class has to have. Technically, the interface only governs syntax, i.e. what methods are there, what arguments they get and what they return. Usually they encapsulate semantics as well, although that only by documentation.
You can then have differen...
Create a CSV File for a user in PHP
...ord2,record3\n";
die;
etc
Edit: Here's a snippet of code I use to optionally encode CSV fields:
function maybeEncodeCSVField($string) {
if(strpos($string, ',') !== false || strpos($string, '"') !== false || strpos($string, "\n") !== false) {
$string = '"' . str_replace('"', '""', $st...
How can I restore the MySQL root user’s full privileges?
I accidentally removed some of the privileges from my MySQL root user, including the ability to alter tables. Is there some way I can restore this user to its original state (with all privileges)?
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