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What is the difference between Integer and int in Java?
...ence to an object of (class) type Integer, or to null.
Java automatically casts between the two; from Integer to int whenever the Integer object occurs as an argument to an int operator or is assigned to an int variable, or an int value is assigned to an Integer variable. This casting is called box...
Postgres manually alter sequence
...But if you feed typed variables to the function you may need explicit type casts to satisfy function type resolution. Like:
SELECT setval(my_text_variable::regclass, my_other_variable::bigint, FALSE);
For repeated operations you might be interested in:
ALTER SEQUENCE payments_id_seq START WITH...
Why do we need boxing and unboxing in C#?
...ble)o;
First we have to explicitly unbox the double ((double)o) and then cast that to an int.
What is the result of the following:
double e = 2.718281828459045;
double d = e;
object o1 = d;
object o2 = e;
Console.WriteLine(d == e);
Console.WriteLine(o1 == o2);
Think about it for a second befor...
Program only crashes as release build — how to debug?
...by a buffer overflow, caused a single byte difference:
char *end = static_cast<char*>(attr->data) + attr->dataSize;
This is a fencepost error (off-by-one error) and was fixed by:
char *end = static_cast<char*>(attr->data) + attr->dataSize - 1;
The weird thing was, I put...
Why unsigned integer is not available in PostgreSQL?
...pret strings as literals, just write '4294966272'::uint4 as your literals. Casts shouldn't be a huge deal either. You don't even need to do range exceptions, you can just treat the semantics of '4294966273'::uint4::int as -1024. Or you can throw an error.
If I wanted this, I would have done it. But...
Generic TryParse
...nverter(typeof(T));
if(converter != null)
{
// Cast ConvertFromString(string text) : object to (T)
return (T)converter.ConvertFromString(input);
}
return default(T);
}
catch (NotSupportedException)
{
return default(T);
}...
Select distinct values from a table field
...t('city').distinct()
This one returns a ValuesListQuerySet which you can cast to a list.
You can also add flat=True to values_list to flatten the results.
See also: Get distinct values of Queryset by field
share
...
Why would finding a type's initializer throw a NullReferenceException?
...found at least 3 workaround approaches for fixing the problem:
Simply by casting the Type to _Type inside the Main method:
var cctor = ((_Type)typeof(Test)).TypeInitializer;
Or making sure that approach 1 was used previously inside the method:
var warmUp = ((_Type)typeof(Test)).TypeInitializer;...
How to see the CREATE VIEW code for a view in PostgreSQL?
...
@elias: just use the version that uses an OID by casting the name to an oid: select pg_get_viewdef('viewname'::regclass, true)
– a_horse_with_no_name
Jan 31 '13 at 20:44
...
“’” showing on page instead of “ ' ”
...h several SQL queries like this...
UPDATE MyTable SET
MyField1 = CONVERT(CAST(CONVERT(MyField1 USING latin1) AS BINARY) USING utf8),
MyField2 = CONVERT(CAST(CONVERT(MyField2 USING latin1) AS BINARY) USING utf8);
Do this for as many tables/columns as necessary.
You can also fix some of these st...