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How to throw a C++ exception
...<< "MyException::~MyException" << endl;
}
virtual const char* what() const throw ()
{
cout << "MyException - what" << endl;
return m_msg.c_str();
}
const string m_msg;
};
void throwDerivedException()
{
cout << "throwDerivedExceptio...
How to COUNT rows within EntityFramework without loading contents?
... where o.ID == '1'
from t in o.MyTable
select t).Count();
Method syntax:
var count = context.MyContainer
.Where(o => o.ID == '1')
.SelectMany(o => o.MyTable)
.Count()
Both generate the same SQL query.
...
How to run a program without an operating system?
...her such weird keys after power-on until you get a boot menu where you can select to boot from the USB.
It is often possible to configure the search order in those menus.
For example, on my T430 I see the following.
After turning on, this is when I have to press Enter to enter the boot menu:
The...
LINQ to SQL - Left Outer Join with multiple join conditions
...g.Where(f => f.otherid == 17).DefaultIfEmpty()
where p.companyid == 100
select f.value
Or you could use a subquery:
from p in context.Periods
join f in context.Facts on p.id equals f.periodid into fg
from fgi in (from f in fg
where f.otherid == 17
select f).DefaultIfE...
Laravel Eloquent: How to get only certain columns from joined tables
...
Change your model to specify what columns you want selected:
public function user() {
return $this->belongs_to('User')->select(array('id', 'username'));
}
And don't forget to include the column you're joining on.
...
How and why does 'a'['toUpperCase']() in JavaScript work?
... same as anyObject.anyPropertyName when anyPropertyName hasn't problematic characters.
See Working with Objects, from the MDN.
The toUpperCase method is attached to the type String. When you call a function on a primitive value, here 'a', it is automatically promoted to an object, here a String :
...
SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
...result set to update is before running the update (same query, just with a select):
select *
from QuestionTrackings q
inner join QuestionAnswers a
on q.AnswerID = a.AnswerID
where q.QuestionID is null -- and other conditions you might want
Particularly whether each answer id has definitely only 1...
how to get the last character of a string?
How to get the last character of the string:
12 Answers
12
...
How do you clear a stringstream variable?
...t, because you avoid invoking the std::string constructor that takes const char*. But any compiler these days should be able to generate the same code in both cases - so I would just go with whatever is more readable.
share
...
jQuery set radio button
...
Your selector looks for the descendant of a input:radio[name=cols] element that has the id of newcol (well the value of that variable).
Try this instead (since you're selecting by ID anyway):
$('#' + newcol).prop('checked',true)...