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sqlite database default time value 'now'
...ime('%s','now'))
);
insert into example(data) values
('foo')
,('bar')
;
select
id
,data
,created_at as epoch
,datetime(created_at, 'unixepoch') as utc
,datetime(created_at, 'unixepoch', 'localtime') as localtime
from example
order by id
;
id|data|epoch |utc |localtime
1 |foo ...
Look up all descendants of a class in Ruby
...e:
class Parent
def self.descendants
ObjectSpace.each_object(Class).select { |klass| klass < self }
end
end
class Child < Parent
end
class GrandChild < Child
end
puts Parent.descendants
puts Child.descendants
puts Parent.descendants gives you:
GrandChild
Child
puts Child.de...
EC2 Instance Cloning
...he easier way is through the web management console:
go to the instance
select the instance and click on instance action
create image
Once you have an image you can launch another cloned instance, data and all. :)
shar...
Parallel foreach with asynchronous lambda
...is:
var bag = new ConcurrentBag<object>();
var tasks = myCollection.Select(async item =>
{
// some pre stuff
var response = await GetData(item);
bag.Add(response);
// some post stuff
});
await Task.WhenAll(tasks);
var count = bag.Count;
If you need something more complex, check o...
How to convert timestamp to datetime in MySQL?
...
SELECT from_unixtime( TIMESTAMP( "2011-12-01", "22:01:23.048" ) ) doesn't work. why? using v5.6
– Janus Troelsen
Feb 4 '14 at 18:44
...
List all indexes on ElasticSearch server?
...
you can also select and order columns adding e.g. &h=health,index as well as sort with &s=health:desc
– Georg Engel
Dec 18 '18 at 19:33
...
iOS 7 TableView like in Settings App on iPad
...)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
if ([cell respondsToSelector:@selector(tintColor)]) {
if (tableView == self.tableView) {
CGFloat cornerRadius = 5.f;
cell.backgroundColor = UIColor.clearColor;
CAShapeLayer *layer = [[CAShapeLayer allo...
How to open a web server port on EC2 instance
...asn't immediately clear to me from the linked instructions, but you should select "Custom TCP". Otherwise you won't be able to change the port.
– KKOrange
Dec 12 '19 at 1:39
a...
Is there a way to navigate to real implementation of method behind an interface?
...
update: as of Visual Studio 2015 update 1, right click on a method and select go to implementation. You can also map it to keyboard shortcut via Tools > Options > Environment > Keyboard and search for Edit.GoToImplementation command. The default shortcut is Ctrl+F12. (F12 will navigate ...
How to do a join in linq to sql with method syntax?
...eOtherClass
on sc.Property1 equals soc.Property2
select new { SomeClass = sc, SomeOtherClass = soc };
Would be equivalent to:
var result = enumerableOfSomeClass
.Join(enumerableOfSomeOtherClass,
sc => sc.Property1,
soc => soc.Property2,
...