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Foreign Key to multiple tables
...g your posted schema:
create table dbo.PartyType
(
PartyTypeId tinyint primary key,
PartyTypeName varchar(10)
)
insert into dbo.PartyType
values(1, 'User'), (2, 'Group');
create table dbo.Party
(
PartyId int identity(1,1) primary key,
PartyTypeId tinyint references dbo.Par...
Erasing elements from a vector
...
Use the remove/erase idiom:
std::vector<int>& vec = myNumbers; // use shorter name
vec.erase(std::remove(vec.begin(), vec.end(), number_in), vec.end());
What happens is that remove compacts the elements that differ from the value to be removed (number_in) ...
Mapping many-to-many association table with extra column(s)
...ntity, and decompose the many to many association between User and Service into two OneToMany associations : One User has many UserServices, and one Service has many UserServices.
You haven't shown us the most important part : the mapping and initialization of the relationships between your entitie...
What is the purpose of Rank2Types?
...the function arrows, the caller must first pick a type for a; if they pick Int, we get f' :: forall r. Num r => (Int -> r) -> Int -> Int -> r, and now we have fixed the g argument so it can take Int but not String. If we enable RankNTypes we can annotate f' with type forall b c r. Num...
How to make an Android Spinner with initial text “Select One”?
...elies on reflection to call the private AdapterView.setNextSelectedPositionInt() and AdapterView.setSelectedPositionInt(), it's not guaranteed to work in future OS updates. It seems likely that it will, but it is by no means guaranteed.
Normally I wouldn't condone something like this, but this ques...
What is the apply function in Scala?
...Every function also has an OO type: for instance, a function that takes an Int parameter and returns an Int will have OO type of Function1[Int,Int].
// define a function in scala
(x:Int) => x + 1
// assign an object representing the function to a variable
val f = (x:Int) => x + 1
Since...
How to extract numbers from a string in Python?
...
If you only want to extract only positive integers, try the following:
>>> str = "h3110 23 cat 444.4 rabbit 11 2 dog"
>>> [int(s) for s in str.split() if s.isdigit()]
[23, 11, 2]
I would argue that this is better than the regex example because you ...
grep a tab in UNIX
...le '\t' , literal TABs (i.e. the ones that look like whitespace) are often converted to SPC when copypasting ...
– plijnzaad
Mar 7 '17 at 11:39
...
Java code for getting current time [duplicate]
...a.time
ZonedDateTime zdt = ZonedDateTime.now();
If needed for old code, convert to java.util.Date. Go through at Instant which is a moment on the timeline in UTC.
java.util.Date date = java.util.Date.from( zdt.toInstant() );
Time Zone
Better to specify explicitly your desired/expected time zo...
Why does C++ require a user-provided default constructor to default-construct a const object?
...
But this still forbids struct A { int n; A() = default; }; const A a; while allowing struct B { int n; B() {} }; const B b; because the new wording still says "user-provided" not "user-declared" and I'm left scratching my head why the committee chose to exclu...