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Why does Oracle 9i treat an empty string as NULL?
...ations arise when '' is being implicitely converted to a VARCHAR2, such as cast('' as char(1)) is null which is... surprisingly TRUE
– sehe
Jul 19 '13 at 15:17
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What's the point of malloc(0)?
...ate memory of correct size. The malloc function is unaware of what you're casting its result to. The malloc function relies purely on the size number that you give as its argument. You need to do malloc(sizeof(int)) to get enough storage to hold an int, for example, not 0.
...
Databinding an enum property to a ComboBox in WPF
... get
{
return Enum.GetValues(typeof(MyEnumType))
.Cast<MyEnumType>();
}
}
In XAML the ItemSource binds to MyEnumTypeValues and SelectedItem binds to SelectedMyEnumType.
<ComboBox SelectedItem="{Binding SelectedMyEnumType}" ItemsSource="{Binding MyEnumTypeVal...
AngularJS HTTP post to PHP and undefined
...
you should cast your result in case $_POST is empty : $_POST = (array) json_decode(file_get_contents('php://input'), true).
– M'sieur Toph'
Oct 12 '14 at 7:12
...
Check if a Class Object is subclass of another Class Object in Java
...
if (o instanceof Number) {
double d = ((Number)o).doubleValue(); //this cast is safe
}
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How do I specify the Linq OrderBy argument dynamically?
...method to be an IOrderedQueryable instead of an IQueryable, you can simply cast the result as follows:
public static IOrderedQueryable<TEntity> OrderBy<TEntity>(this IQueryable<TEntity> source, string orderByProperty, bool desc)
{
string command = desc ? "OrderByDescending" :...
Select between two dates with Django
... Filtering with dates won’t include items on the last day.
You need to casts the value as date:
...filter(created_at__date__range=(start_date, end_date))
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How to do an instanceof check with Scala(Test)
...r needs. I would recommend it in those cases because it gives you the typecasting for free and leaves less room for error.
Example:
OuterType foo = blah
foo match {
case subFoo : SubType => {
subFoo.thingSubTypeDoes // no need to cast, use match variable
}
case subFoo => {
// ...
Best way to get identity of inserted row?
...
Add
SELECT CAST(scope_identity() AS int);
to the end of your insert sql statement, then
NewId = command.ExecuteScalar()
will retrieve it.
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How to avoid the “divide by zero” error in SQL?
...of the first argument. This altered example works fine: SELECT 1 / NULLIF(CAST(NULL AS INT), 0). In real life, you are going to supply a table column to NULLIF() rather than a NULL constant. Since table columns have known datatypes, this also works fine: SELECT 1 / NULLIF(SomeNullableColumn, 0) F...