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How does MySQL process ORDER BY and LIMIT in a query?
...t used it in a production environment, but now when I bench marked it, the extra sorting does not impact the performance.
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Calendar Recurring/Repeating Events - Best Storage Method
...e | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+--------+---------------+---------+---------+------------------+------+--------------------------------+
| 1 | SIMPLE | EM1 | ALL | NULL | NULL ...
Max return value if empty query
...tion "Sequence contains no elements"
class Program
{
static void Main(string[] args)
{
List<MyClass> list = new List<MyClass>();
list.Add(new MyClass() { Value = 2 });
IEnumerable<MyClass> iterator = list.Where(x => x.Value == 3); // empty iter...
scheduleAtFixedRate vs scheduleWithFixedDelay
...
I could not understand the "extra" word mentioned in scheduleAtFixedRate time series diagram.
– MuneshSingh
Mar 25 '18 at 6:39
1
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How do Mockito matchers work?
...dummy value, like 0 for anyInt() or any(Integer.class) or an empty List<String> for anyListOf(String.class). Because of type erasure, though, Mockito lacks type information to return any value but null for any() or argThat(...), which can cause a NullPointerException if trying to "auto-unbox" ...
RAII and smart pointers in C++
...ance (and stealing an example from another answer):
void foo() {
std::string str;
// Do cool things to or using str
}
This works fine - but what if we want to return str? We could write this:
std::string foo() {
std::string str;
// Do cool things to or using str
return str;
}...
How to vertically center divs? [duplicate]
...ng with a 'display: inline-box'. The line-height of the contents can cause extra space below the inline-box, and the result is that the child is aligned slightly above centre. I am not sure what part of the html spec causes this, but I found it to be unobvious and it took a while to work out the rea...
Django class-based view: How do I pass additional parameters to the as_view method?
...m urls.py
https://docs.djangoproject.com/en/1.7/topics/http/urls/#passing-extra-options-to-view-functions
This also works for generic views. Example:
url(r'^$', views.SectionView.as_view(), { 'pk': 'homepage', 'another_param':'?'}, name='main_page'),
In this case the parameters passed to the vi...
How to convert TimeStamp to Date in Java?
...s").parse("01/01/1970 01:00:00").getTime() / 1000;
Or the opposite:
String date = new java.text.SimpleDateFormat("MM/dd/yyyy HH:mm:ss").format(new java.util.Date (epoch*1000));
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C++ preprocessor __VA_ARGS__ number of arguments
...GS__})/sizeof(int))
Full example:
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#define NUMARGS(...) (sizeof((int[]){__VA_ARGS__})/sizeof(int))
#define SUM(...) (sum(NUMARGS(__VA_ARGS__), __VA_ARGS__))
void sum(int numargs, ...);
int main(int argc, char *argv[]...