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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...
IMHO, the reason why 2 queries
SELECT * FROM count_test WHERE b = 666 ORDER BY c LIMIT 5;
SELECT count(*) FROM count_test WHERE b = 666;
are faster than using SQL_CALC_FOUND_ROWS
SELECT SQL_CALC_FOUND_ROWS * FROM count_test WHERE b = 555 ORDER BY c LIMIT 5;
has to be see...
What is the Scala identifier “implicitly”?
...
This answer would be updated for the latest version.
– emeth
Oct 14 '14 at 2:58
1
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Does Python have a ternary conditional operator?
...
You can index into a tuple:
(falseValue, trueValue)[test]
test needs to return True or False.
It might be safer to always implement it as:
(falseValue, trueValue)[test == True]
or you can use the built-in bool() to assure a Boolean value:
(falseValue, trueValue)[bool(<...
How is “=default” different from “{}” for default constructor and destructor?
...structor, then things won't compile whether or not you destruct a Widget:
test.cpp:8:7: error: field of type 'A' has private destructor
A a_;
^
test.cpp:4:5: note: declared private here
~A();
^
1 error generated.
...
How do I run Python code from Sublime Text 2?
... the reference to Python in path.
[cmd: [u'python', u'-u', u'C:\\scripts\\test.py']]
[path: ...;C:\Python27 32bit;...]
The point is that it tries to run python via command line, the cmd looks like:
python -u C:\scripts\test.py
If you can't run python from cmd, Sublime Text can't too.
(Try it your...
Determine if Android app is being used for the first time
... ...
}
// ...
}
The basic logic can be verified using this JUnit test:
public void testCheckAppStart() {
// First start
int oldVersion = -1;
int newVersion = 1;
assertEquals("Unexpected result", AppStart.FIRST_TIME,
service.checkAppStart(newVersion, oldVersion)...
How can I render inline JavaScript with Jade / Pug?
...an example of what i'm trying to do, but it won't compile. I'm using the latest release too.
– JMWhittaker
May 2 '11 at 17:24
...
How to execute a Python script from the Django shell?
...py
commands/
__init__.py
my_command.py
tests.py
views.py
and in this file define your custom command (ensuring that the name of the file is the name of the command you want to execute from ./manage.py)
from django.core.management.base import BaseCommand
cl...
Possible heap pollution via varargs parameter
...led with List[] non-varargs type.
Here is an example:
public static void testCode(){
List[] b = new List[1];
test(b);
}
@SafeVarargs
public static void test(List<A>... a){
}
As you can see List[] b can contain any type of consumer, and yet this code compiles. If you use varargs, t...
Does Python have “private” variables in classes?
...ariation of private variables in the underscore convention.
In [5]: class Test(object):
...: def __private_method(self):
...: return "Boo"
...: def public_method(self):
...: return self.__private_method()
...:
In [6]: x = Test()
In [7]: x.public_method(...