How to have a sql_variant parameter for a SQL CLR stored procedure?

Question

How can one add a sql_variant parameter to a SQL CLR stored procedure? Using System.Object does not work, and I don't see any attributes that I can use.

[Microsoft.SqlServer.Server.SqlProcedure]
public static void ClearOnePartition(
    SqlString aString
    , /* I want this to be a sql_variant */ object aVariant
)
{
    //do stuff here
}

Answer 1

In Mapping CLR Parameter Data from SQL Books Online, Object is listed as the correct type to use to map sql_variant .

I created a simple SQL Server project and added the following class to it:

public partial class StoredProcedures
{
    [Microsoft.SqlServer.Server.SqlProcedure]
    public static void StoredProcedure1(object param1)
    {
        // Put your code here
        //Trace.Write(param1);
        SqlContext.Pipe.Send(param1.ToString());

    }
};

I then modified the test.sql file to exercise this stored proc:

DECLARE @thing sql_variant = 'hahahahaha';

EXEC dbo.StoredProcedure1 @thing

This runs as expected and produces the following output:

hahahahaha

No rows affected.

(0 row(s) returned)

Finished running sp_executesql.

Answer 2

Partition Boundary values, as shown in the CREATE PARTITION FUNCTION documentation, can be one of many different types:

All data types are valid for use as partitioning columns, except text, ntext, image, xml, timestamp, varchar(max), nvarchar(max), varbinary(max), alias data types, or CLR user-defined data types.

And their actual datatype is stored in sys.partition_parameters .

But if one is selecting them out of sys.partition_range_values , then the value field is of type SQL_VARIANT (and for good reason, obviously).

Yes, SQL_VARIANT (as already stated) maps to object in .NET.

If you need to check for NULLs, compare the object to DBNull.Value .

If you want to know the underlying type of the value in the object (it most likely isn't going to be SQL_VARIANT / object ), use the GetType() method:

if (aVariant.GetType() == typeof(SqlInt16))