create function sap_newid (@max_id integer)
returns integer
as begin
 declare @i integer
 set @i = @max_id/ 300 * 300 +@@spid --целочисленное деление
 return case when @i>@max_id then @i else @i+ 300  end
end

select dbo.sap_newid( 1 )

select dbo.sap_newid( 1 ) into :i from sysobjects where id= 1 ;

SELECT SCOPE_IDENTITY() AS [SCOPE_IDENTITY]

create function sap_syso (@max_id integer)
returns @aTable table (id int, name sysname)
as begin
 insert @aTable select id, name from sysobjects where sysobjects.id<@max_id
 return
end

int i, max_id= 10 

select count(id) into :i from dbo.sap_syso(:max_id);