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Using current time in UTC as default value in PostgreSQL
...rap it in a function:
create function now_utc() returns timestamp as $$
select now() at time zone 'utc';
$$ language sql;
create temporary table test(
id int,
ts timestamp without time zone default now_utc()
);
shar...
Class with Object as a parameter
... Table to be a new-style class (as opposed to "classic" class).
In Python3 all classes are new-style classes, so this is no longer necessary.
New style classes have a few special attributes that classic classes lack.
class Classic: pass
class NewStyle(object): pass
print(dir(Classic))
# ['__doc__...
What does functools.wraps do?
... def with_logging(*args, **kwargs):
print(func.__name__ + " was called")
return func(*args, **kwargs)
return with_logging
then when you say
@logged
def f(x):
"""does some math"""
return x + x * x
it's exactly the same as saying
def f(x):
"""does some math"""
...
How to change folder with git bash?
...
Go to the directory manually and do right click → Select 'Git bash' option.
Git bash terminal automatically opens with the intended directory. For example, go to your project folder. While in the folder, right click and select the option and 'Git bash'. It will open automat...
How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
...
Copy all the lines to clipboard
...
on Mac
copy selected part: visually select text(type v or V in normal
mode) and type :w !pbcopy
copy the whole file :%w !pbcopy
past from the clipboard :r !pbpaste
...
HTTPS setup in Amazon EC2
... of your project
On Load Balancer Protocol add Http and Https
Next > Select exiting security group
Choose the security group that you have create in the previous step
Next > Choose certificate from ACM
Select the certificate of the step 1
Next >
on Health check i've used the ping p...
Bootstrap 3 Slide in Menu / Navbar on Mobile [closed]
...%';
$("#slide-nav").on("click", toggler, function (e) {
var selected = $(this).hasClass('slide-active');
$('#slidemenu').stop().animate({
left: selected ? menuneg : '0px'
});
$('#navbar-height-col').stop().animate({
left: selected ? sl...
Android Studio: how to attach Android SDK sources?
...uild.gradle with the desired API level.
In the Project window on the left, select the External Libraries drop-down.
Right click the menu item and select Open Library Settings.
Click the Sourcepath tab and use the + icon at the bottom left to link to the desired SDK sources (should be in something/s...
Simple way to convert datarow array to datatable
...For .Net Framework 3.5+
DataTable dt = new DataTable();
DataRow[] dr = dt.Select("Your string");
DataTable dt1 = dr.CopyToDataTable();
But if there is no rows in the array, it can cause the errors such as The source contains no DataRows. Therefore, if you decide to use this method CopyToDataTable...