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When do I use fabs and when is it sufficient to use std::abs?
...t, long, long long, std::intmax_t, float, double, long double. No short or char versions (or unsigned versions) that I can see.
– user673679
Mar 2 at 17:41
...
How do I temporarily disable triggers in PostgreSQL?
...ct = 'disable';
else
act = 'enable';
end if;
for r in select c.relname from pg_namespace n
join pg_class c on c.relnamespace = n.oid and c.relhastriggers = true
where n.nspname = nsp
loop
execute format('alter table %I %s trigger all', r.relname, act)...
How to get the index of an item in a list in a single step?
...g different (e.g. on top of any IEnumerable<>).
Use the overload of Select which takes an index in the predicate, so you transform your list into an (index, value) pair:
var pair = myList.Select((Value, Index) => new { Value, Index })
.Single(p => p.Value.Prop == oProp...
Add 2 hours to current time in MySQL?
...
SELECT *
FROM courses
WHERE DATE_ADD(NOW(), INTERVAL 2 HOUR) > start_time
See Date and Time Functions for other date/time manipulation.
share
...
How to write UPDATE SQL with Table alias in SQL Server 2008?
... Mark Byers - Great Answer!! This syntax allows me to add a commented out Select statement, which allows me to test the update by doing the select first (highlight from the select down and execute): SET Q.TITLE = 'TEST' -- SELECT *
– user1636464
Aug 30 '12 at ...
Combine :after with :hover
I want to combine :after with :hover in CSS (or any other pseudo selector). I basically have a list and the item with the selected class has an arrow shape applied using :after . I want the same to be true for objects that are being hovered over but cant quite get it to work. Heres the cod...
What are C++ functors and their uses?
...te:
class SomeClass
{
std::string state_;
public:
SomeClass(const char* s) : state_(s) {}
void method( std::string param )
{
std::cout << state_ << param << std::endl;
}
};
SomeClass *inst = new SomeClass("Hi, i am ");
boost::function< void (std::st...
How to get a group of toggle buttons to act like radio buttons in WPF?
...ike toggle buttons, but also as radio buttons where only one button can be selected / pressed down at a current time. It also need to have a state where none of the buttons are selected / pressed down.
...
URL Encode a string in jQuery for an AJAX request
... Resource Identifier (URI) component by replacing each instance of certain characters by one, two, three, or four escape sequences representing the UTF-8 encoding of the character (will only be four escape sequences for characters composed of two "surrogate" characters).
Example:
var encoded = en...
How to map calculated properties with JPA and Hibernate
...e float finalPrice;
Or even complex queries on other tables:
@Formula("(select min(o.creation_date) from Orders o where o.customer_id = id)")
private Date firstOrderDate;
Where id is the id of the current entity.
The following blog post is worth the read: Hibernate Derived Properties - Perform...