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PostgreSQL: Which Datatype should be used for Currency?
... have to deal with multiple currencies you'll need that much precision for converting. No matter what I'm presenting a user, I always store to US Dollar. In that way I can readily convert to any other currency, given the conversion rate for the day involved.
If you never do anything but one curre...
Test whether string is a valid integer
...n enough: Parse user input in a shell script. If the user provided a valid integer, the script does one thing, and if not valid, it does something else. Trouble is, I haven't found an easy (and reasonably elegant) way of doing this - I don't want to have to pick it apart char by char.
...
Should I instantiate instance variables on declaration or in the constructor?
...tructor or constructors for the class. The initialization code is inserted into a constructor in the order it appears in the source code, which means that a field initializer can use the initial values of fields declared before it.
Additionally, you might want to lazily initialize your field. In c...
How can I represent an 'Enum' in Python?
...TWO')
>>> Numbers.ZERO
0
>>> Numbers.ONE
1
Support for converting the values back to names can be added this way:
def enum(*sequential, **named):
enums = dict(zip(sequential, range(len(sequential))), **named)
reverse = dict((value, key) for key, value in enums.iteritems(...
Cocoa: What's the difference between the frame and the bounds?
... height) positioned at 25,25 (x,y) of its superview. The following code prints out this view's bounds and frame:
// This method is in the view controller of the superview
- (void)viewDidLoad {
[super viewDidLoad];
NSLog(@"bounds.origin.x: %f", label.bounds.origin.x);
NSLog(@"bounds.or...
Comparing strings by their alphabetical order
...ethod.
s1.compareTo(s2)
From the javadocs:
The result is a negative integer if
this String object lexicographically
precedes the argument string. The
result is a positive integer if this
String object lexicographically
follows the argument string. The
result is zero if the strings...
Implicit “Submit” after hitting Done on the keyboard at the last EditText
...Listener() {
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
if (actionId == EditorInfo.IME_ACTION_DONE) {
submit_btn.performClick();
return true;
}
return false;
}
});
Where submit_btn is your...
How to remove all the occurrences of a char in c++ string
...nclude <string>
#include <iostream>
#include <algorithm>
int main() {
std::string s1 = "a1a2b3c4a5";
char s2[256];
std::copy_if(s1.begin(), s1.end(), s2, [](char c){return c!='a';});
std::cout << s2 << std::endl;
return 0;
}
...
Check if a row exists, otherwise insert
...begin
drop table Bookings
end
GO
create table Bookings(
FlightID int identity(1, 1) primary key,
TicketsMax int not null,
TicketsBooked int not null
)
GO
insert Bookings(TicketsMax, TicketsBooked) select 1, 0
insert Bookings(TicketsMax, TicketsBooked) select 2, 2
insert Bookings...
How to get HTTP response code for a URL in Java?
...enConnection();
connection.setRequestMethod("GET");
connection.connect();
int code = connection.getResponseCode();
This is by no means a robust example; you'll need to handle IOExceptions and whatnot. But it should get you started.
If you need something with more capability, check out HttpClient...