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Insert, on duplicate update in PostgreSQL?
...it would be much slower, because each upsert would be its' own individual call into the database.
– baash05
Mar 1 '12 at 0:27
...
std::vector performance regression when enabling C++11
I have found an interesting performance regression in a small C++ snippet, when I enable C++11:
1 Answer
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find -exec with multiple commands
...e? this is failing: find ./* -exec grep -v 'COLD,' {} \; -exec egrep -i "my_string" {} \;
– rajeev
Jan 22 '13 at 16:08
53
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What is dynamic programming? [closed]
...ith dynamic programming, you store your results in some sort of table generally. When you need the answer to a problem, you reference the table and see if you already know what it is. If not, you use the data in your table to give yourself a stepping stone towards the answer.
The Cormen Algorithms ...
Where is Maven' settings.xml located on mac os?
...8:00)
Maven home: /usr/local/Cellar/maven/3.5.0/libexec
Java version: 1.8.0_121, vendor: Oracle Corporation
Java home: /Library/Java/JavaVirtualMachines/jdk1.8.0_121.jdk/Contents/Home/jre
Default locale: zh_CN, platform encoding: UTF-8
OS name: "mac os x", version: "10.11.5", arch: "x86_64", family:...
How can I declare and define multiple variables in one line using C++?
I always though that if I declare these three variables that they will all have the value 0
10 Answers
...
Assignment in an if statement
... = value as T;
if (t != null)
{
action(t);
}
}
Then call it with:
animal.AsIf<Dog>(dog => {
// Use dog in here
});
Alternatively, you could combine the two:
public static void AsIf<T>(this object value, Action<T> action) where T : class
{
// EVI...
AttributeError: 'module' object has no attribute 'urlopen'
...
A Python 2+3 compatible solution is:
import sys
if sys.version_info[0] == 3:
from urllib.request import urlopen
else:
# Not Python 3 - today, it is most likely to be Python 2
# But note that this might need an update when Python 4
# might be around one day
from urlli...
Force page scroll position to top at page refresh in HTML
... This is the correct answer. The jQuery solution does not work in all cases.
– Harry Stevens
Dec 5 '17 at 18:52
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What is the use of “assert” in Python?
...t True # nothing happens
>>> assert False
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
Assertions can include an optional message, and you can disable them when running the interpreter.
To print a message if the assertion fails:
ass...