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How to filter SQL results in a has-many-through relation
...on easier to extend to n clubs and that avoids INTERSECT (not available in MySQL) and IN (as performance of this sucks in MySQL)
SELECT s.id,
s.name
FROM student s
join student_club sc
ON s.id = sc.student_id
WHERE sc.club_id IN ( 30, 50 )
GROUP BY s.id,
s.name
...
Sass combining parent using ampersand (&) with type selectors
...his has been possible since Sass 3.3.0.rc.1 (Maptastic Maple).
The @at-root directive causes one or more rules to be emitted at the root of the document, rather than being nested beneath their parent selectors.
We can combine the @at-root directive along with interpolation #{} to arrive at the...
How do I clone a subdirectory only of a Git repository?
I have my Git repository which, at the root, has two sub directories:
18 Answers
18
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IN vs OR in the SQL WHERE Clause
...')
WHERE foo = 'a' OR foo = 'b' OR foo = 'c'
According to the manual for MySQL if the values are constant IN sorts the list and then uses a binary search. I would imagine that OR evaluates them one by one in no particular order. So IN is faster in some circumstances.
The best way to know is to p...
windowSoftInputMode=“adjustResize” not working with translucent action/navbar
...missing the following property:
android:fitsSystemWindows="true"
in the root RelativeLayout of the fragment .xml layout.
Update:
Last year there was an interesting talk by Chris Bane that explains in good detail how this works:
https://www.youtube.com/watch?v=_mGDMVRO3iE
...
Trust Anchor not found for Android SSL Connection
...ated cert, but for one (like the OP's) which has a valid chain back to the root CA's it is just a workaround for a badly configured server - see my answer.
– Stevie
Apr 30 '13 at 14:43
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Select top 10 records for each category
...d
HAVING COUNT(*) <= 10;
update: This example of GROUP BY works in MySQL and SQLite only, because those databases are more permissive than standard SQL regarding GROUP BY. Most SQL implementations require that all columns in the select-list that aren't part of an aggregate expression are al...
In Django, how does one filter a QuerySet with dynamic field lookups?
...ed on a poor design is more expensive and complex than necessary. Solving root-cause problems is better than solving other problems that stem from bad design decisions. I'm sorry you don't like root-cause analysis. But when something's really hard, it usually means you're trying the wrong thing t...
IntelliJ does not show project folders
...hat pops up, click on the "..." next button which takes you to the Content root. Find your root folder and select it
Click the "ok" button
Ignore any warning that says the name is already in use
share
|
...
When to use inline function and when not to use it?
... most important rule of optimization is that premature optimization is the root of all evil. Always write clear code (using efficient algorithms), then profile your program and only optimize functions that are taking too long.
If you find a particular function is very short and simple, and it's ge...