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What does the “at” (@) symbol do in Python?
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12 Answers
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How to easily truncate an array with JavaScript?
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edited May 21 '15 at 1:37
David Mason
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
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This reduces the number of round-trips to the database from N+1 to 2.
Most ORM tools give you several ways to prevent N+1 selects.
Reference: Java Persistence with Hibernate, chapter 13.
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Convert light frequency to RGB?
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answered Sep 24 '09 at 15:47
Stephen MesaStephen Mesa
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Update multiple rows in same query using PostgreSQL
...zable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c = c.column_c
from (values
('123...
Error type 3 Error: Activity class {} does not exist
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What is the iPad user agent?
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Mozilla/5.0(iPad; U; CPU iPhone OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, l...
How to display a list inline using Twitter's Bootstrap
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Bootstrap 2.3.2
<ul class="inline">
<li>...</li>
</ul>
Bootstrap 3
<ul class="list-inline">
<li>...</li>
</ul>
Bootstrap 4
<ul class="list-inline">
<li class="list-...
Find the nth occurrence of substring in a string
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21 Answers
21
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How to flush output of print function?
... an optional flush argument
print("Hello world!", flush=True)
On Python 2 you'll have to do
import sys
sys.stdout.flush()
after calling print. By default, print prints to sys.stdout (see the documentation for more about file objects).
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