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What is the difference between an expression and a statement in Python?
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248
Expressions only contain identifiers, literals and operators, where operators include arithmet...
What does the “at” (@) symbol do in Python?
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12 Answers
12
Active
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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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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...
How to compare versions in Ruby?
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234
Gem::Version.new('0.4.1') > Gem::Version.new('0.10.1')
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What is Func, how and when is it used
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edited Sep 2 '10 at 7:58
answered Sep 2 '10 at 7:48
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How do I remove duplicate items from an array in Perl?
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edited Jun 21 '14 at 1:39
Miller
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Javascript shorthand ternary operator
...g for, where it defaults if undefined?
var foo = bar || 1; // 1
var bar = 2;
foo = bar || 1; // 2
By the way, this works for a lot of scenarios, including objects:
var foo = bar || {}; // secure an object is assigned when bar is absent
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Convert datetime object to a String of date only in Python
...o help you format your date.
E.g.,
import datetime
t = datetime.datetime(2012, 2, 23, 0, 0)
t.strftime('%m/%d/%Y')
will yield:
'02/23/2012'
More information about formatting see here
share
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Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
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277
Try to start the MySQL server:
mysql.server start
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