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SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?
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select COUNT_BIG(*) FROM Traffic t CROSS JOIN Recipient r and SELECT COUNT_BIG(*) FROM Traffic t FULL JOIN Recipient r ON (1=1) they are the same.
– urlreader
Sep 20 '13 at 21:02
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Given two directory trees, how can I find out which files differ by content?
...-dereference --new-file --no-ignore-file-name-case /dir1 /dir2 > dirdiff_1.txt
rsync --recursive --delete --links --checksum --verbose --dry-run /dir1/ /dir2/ > dirdiff_2.txt
The choice between them depends on the location of dir1 and dir2:
When the directories reside on two seperate drive...
Python: Find in list
...n or generator expressions for that:
matches = [x for x in lst if fulfills_some_condition(x)]
matches = (x for x in lst if x > 6)
The latter will return a generator which you can imagine as a sort of lazy list that will only be built as soon as you iterate through it. By the way, the first one...
Embedded MongoDB when running integration tests
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public class EmbeddedMongoTest
{
private static final String DATABASE_NAME = "embedded";
private MongodExecutable mongodExe;
private MongodProcess mongod;
private MongoClient mongo;
@Before
public void beforeEach() throws Exception {
MongodStarter starter = Mongod...
What do I have to do to get Core Data to automatically migrate models?
...hBool:YES], NSInferMappingModelAutomaticallyOption, nil];
NSError *error;
_persistentStoreCoordinator = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel: [self managedObjectModel]];
if (![_persistentStoreCoordinator addPersistentStoreWithType:NSSQLiteStoreType configuration:nil URL...
How to initialize static variables
...xample: class Foo {public static $bar = array(3 * 4, "b" => 7 + 8);} var_dump(Foo::$bar);
– Pang
May 8 '15 at 2:29
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show 3 more comments...
Ruby, remove last N characters from a string?
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Ruby 2.5+
As of Ruby 2.5 you can use delete_suffix or delete_suffix! to achieve this in a fast and readable manner.
The docs on the methods are here.
If you know what the suffix is, this is idiomatic (and I'd argue, even more readable than other answers here):
'abc...
How to pass json POST data to Web API method as an object?
...w code will work fine (tested)
$(function () {
var customer = {contact_name :"Scott",company_name:"HP"};
$.ajax({
type: "POST",
data :JSON.stringify(customer),
url: "api/Customer",
contentType: "application/json"
});
});
Result
contentType property t...
Perl build, unit testing, code coverage: A complete working example
...}
sub repeat {
return 1;
}
sub argumentTest {
my ($booleanArg) = @_;
if (!defined($booleanArg)) {
return "null";
}
elsif ($booleanArg eq "false") {
return "false";
}
elsif ($booleanArg eq "true") {
return "true";
}
else {
return "...
Templated check for the existence of a class member function?
...truct Generic {};
// SFINAE test
template <typename T>
class has_helloworld
{
typedef char one;
struct two { char x[2]; };
template <typename C> static one test( decltype(&C::helloworld) ) ;
template <typename C> static two test(...);
public:
enum...