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SQL “select where not in subquery” returns no results
...e efficient, since LEFT JOIN / IS NULL cannot be optimized to an ANTI JOIN by its optimizer.
In PostgreSQL, LEFT JOIN / IS NULL and NOT EXISTS are more efficient than NOT IN, sine they are optimized to an Anti Join, while NOT IN uses hashed subplan (or even a plain subplan if the subquery is too la...
The SQL OVER() clause - when and why is it useful?
...d why I need it.
What does the function Over do? What does Partitioning By do?
Why can't I make a query with writing Group By SalesOrderID ?
...
PostgreSQL delete with inner join
... The best answer, especially the first one, as it allows you to match by multiple fields.
– Kostanos
Nov 14 '17 at 14:58
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Get user profile picture by Id
... how I'll be able to get a direct link to a profile picture of a user only by using his id?
15 Answers
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How to change the session timeout in PHP?
...ents are not malicious, you can set an upper bound on the session duration by tweaking certain parameters. If you are using PHP's default session handling with cookies, setting session.gc_maxlifetime along with session_set_cookie_params should work for you like this:
// server should keep session da...
How to annotate MYSQL autoincrement field with JPA annotations
...=GenerationType.IDENTITY)
private Long id;
The other 2 approaches stated by Pascal in his answer were not working for me.
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How do I set the offset for ScrollSpy in Bootstrap?
...eventDefault();
$($(this).attr('href'))[0].scrollIntoView();
scrollBy(0, -offset);
});
I found it here: https://github.com/twitter/bootstrap/issues/3316
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How to implement a many-to-many relationship in PostgreSQL?
...;
I made a few adjustments:
The n:m relationship is normally implemented by a separate table - bill_product in this case.
I added serial columns as surrogate primary keys. In Postgres 10 or later consider an IDENTITY column instead. See:
Safely rename tables using serial primary key columns
Auto...
python list in sql query as parameter
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Why do you want to join "by hand" rather than leave this work to the dbapi? the key is to use a tuple rather than a list...
– Alessandro Dentella
Jan 11 '17 at 9:24
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How to get the currently logged in user's user id in Django?
...E_CLASSES setting.
The current user is in request object, you can get it by:
def sample_view(request):
current_user = request.user
print current_user.id
request.user will give you a User object representing the currently logged-in user. If a user isn't currently logged in, request.user ...