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What are naming conventions for MongoDB?
...tation mentions you may use underscores, also built-in identifier is named _id (but this may be be to indicate that _id is intended to be private, internal, never displayed or edited.
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impro...
Why does comparing strings using either '==' or 'is' sometimes produce a different result?
... 23yr old Jack, but its not the same person.
class Person(object):
def __init__(self, name, age):
self.name = name
self.age = age
def __eq__(self, other):
return self.name == other.name and self.age == other.age
jack1 = Person('Jack', 23)
jack2 = Person('Jack', 23)
jac...
What does `someObject.new` do in Java?
... dup
4: invokespecial #3; //Method "<init>":()V
7: astore_1
8: new #4; //class Test$TestInner
11: dup
12: aload_1
13: dup
14: invokevirtual #5; //Method java/lang/Object.getClass:()Ljava/lang/Class;
17: pop
18: invokespecial #6; //Method Test$Te...
How do you determine the size of a file in C?
...ject's code:
#include <sys/stat.h>
#include <sys/types.h>
off_t fsize(const char *filename) {
struct stat st;
if (stat(filename, &st) == 0)
return st.st_size;
return -1;
}
Changes:
Made the filename argument a const char.
Corrected the struct stat defini...
WARN Could not determine content-length of response body. Set content-length of the response or set
...d of Webrick, and the warn will disappear.
– fearless_fool
Aug 3 '12 at 3:55
2
I second using thi...
How do I set bold and italic on UILabel of iPhone/iPad?
...t {
return with([.traitBold, .traitItalic])
}
func with(_ traits: UIFontDescriptor.SymbolicTraits...) -> UIFont {
guard let descriptor = self.fontDescriptor.withSymbolicTraits(UIFontDescriptor.SymbolicTraits(traits).union(self.fontDescriptor.symbolicTraits)) else {
...
How to retry after exception?
... a nice way to retry a block of code on failure.
For example:
@retry(wait_random_min=1000, wait_random_max=2000)
def wait_random_1_to_2_s():
print("Randomly wait 1 to 2 seconds between retries")
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...
How to combine two or more querysets in a Django view?
... pagination on the search result list, I would like to use a generic object_list view to display the results. But to do that, I have to merge 3 querysets into one.
...
LEFT JOIN only first row
...
If you can assume that artist IDs increment over time, then the MIN(artist_id) will be the earliest.
So try something like this (untested...)
SELECT *
FROM feeds f
LEFT JOIN artists a ON a.artist_id = (
SELECT
MIN(fa.artist_id) a_id
FROM feeds_artists fa
WHERE fa.feed_id = ...
How to use clock() in C++
...#include <cstdio>
#include <ctime>
int main() {
std::clock_t start;
double duration;
start = std::clock();
/* Your algorithm here */
duration = ( std::clock() - start ) / (double) CLOCKS_PER_SEC;
std::cout<<"printf: "<< duration <<'\n';
}
...