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Are there any disadvantages to always using nvarchar(MAX)?
...E @SomeString NVARCHAR(10),
@StartTime DATETIME;
--=====
SELECT @startTime = GETDATE();
SELECT TOP 1000000
@SomeString = 'ABC'
FROM master.sys.all_columns ac1,
master.sys.all_columns ac2;
SELECT testTime='10', Duration = DATEDIFF(ms,@StartTime,GETDATE());
GO
--...
How to rethrow the same exception in SQL Server
...lare @ErrorMessage nvarchar(max), @ErrorSeverity int, @ErrorState int;
select @ErrorMessage = ERROR_MESSAGE() + ' Line ' + cast(ERROR_LINE() as nvarchar(5)), @ErrorSeverity = ERROR_SEVERITY(), @ErrorState = ERROR_STATE();
if @@trancount > 0 rollback transaction;
raiserror (@ErrorMessa...
Python 3 turn range to a list
... This is definitely the way to go, but a nitpick: this isn't really a "cast"
– jterrace
Jul 14 '12 at 1:03
@jterra...
How can I easily convert DataReader to List? [duplicate]
... writing an extension method for this:
public static IEnumerable<T> Select<T>(this IDataReader reader,
Func<IDataReader, T> projection)
{
while (reader.Read())
{
yield return projection(reader);
}
}
You can then use LINQ...
Enum “Inheritance”
... int values to the constants as defined in the existing enum, then you can cast between the enum and the constants, e.g:
public enum SomeEnum // this is the existing enum (from WSDL)
{
A = 1,
B = 2,
...
}
public class Base
{
public const int A = (int)SomeEnum.A;
//...
}
public c...
jQuery Data vs Attr?
...should be preferred.
The .data() method will also perform some basic auto-casting if the value matches a recognized pattern:
HTML:
<a id="foo"
href="#"
data-str="bar"
data-bool="true"
data-num="15"
data-json='{"fizz":["buzz"]}'>foo!</a>
JS:
$('#foo').data('str')...
How to check if a database exists in SQL Server?
...script:
DECLARE @dbname nvarchar(128)
SET @dbname = N'Senna'
IF (EXISTS (SELECT name
FROM master.dbo.sysdatabases
WHERE ('[' + name + ']' = @dbname
OR name = @dbname)))
-- code mine :)
PRINT 'db exists'
share
...
constant pointer vs pointer on a constant value [duplicate]
...is constant and immutable but the pointed data is not.
You could use const_cast(in C++) or c-style cast to cast away the constness in this case as data itself is not constant.
const char * a;
means that the pointed data cannot be written to using the pointer a.
Using a const_cast(C++) or c-style ...
Convert Decimal to Double
...
An explicit cast to double like this isn't necessary:
double trans = (double) trackBar1.Value / 5000.0;
Identifying the constant as 5000.0 (or as 5000d) is sufficient:
double trans = trackBar1.Value / 5000.0;
double trans = trackBar1...
What is object slicing?
...
@Felix Thanks but I don't think casting back (since not a pointer arithmetic) will work , A a = b; a is now object of type A which has copy of B::foo. It will be mistake to cast it back now i think.
– user72424
Aug 12 ...