inline table-valued function vs scalar function -- simple test, Sql Server

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/*
[When is a SQL function not a function? "If it’s not inline, it’s rubbish." - Rob Farley](http://sqlblog.com/blogs/rob_farley/archive/2011/11/08/when-is-a-sql-function-not-a-function.aspx)
[Inline Scalar Functions - Itzik Ben-Gan](http://sqlmag.com/sql-server/inline-scalar-functions)
[Scalar functions, inlining, and performance: An entertaining title for a boring post - Adam Machanic](http://sqlblog.com/blogs/adam_machanic/archive/2006/08/04/scalar-functions-inlining-and-performance-an-entertaining-title-for-a-boring-post.aspx)
[TSQL User-Defined Functions: Ten Questions You Were Too Shy To Ask - Robert Sheldon](https://www.simple-talk.com/sql/sql-training/tsql-user-defined-functions-ten-questions-you-were-too-shy-to-ask/)
*/

CREATE Function [dbo].[udf-Stat-Round-To](@Value float,@Round float)
Returns Float
As
Begin
Return case when @Round=0 then NULL else Floor(@Value)+Floor((@Value-Floor(@Value))/@Round)*@Round end
End
go
CREATE Function [dbo].[udtvf-Stat-Round-To](@Value float,@Round float)
Returns table as return
select  StatRoundTo = case when @Round=0 then NULL 
    else Floor(@Value)+Floor((@Value-Floor(@Value))/@Round)*@Round 
    end
go

create table gd (what varchar(16), ended datetime2(7))
create table t (col float);

with a as (select n from (values(0),(1),(2),(3),(4),(5),(6),(7),(8),(9)) t(n))
, numbers as (
  select n = row_number() over (order by (select 1))-1
    from         a as deka
      cross join a as hecto
      cross join a as kilo
      cross join a as [tenK]
      cross join a as [hundredk]
      --cross join a as mega
    )
insert into t
select
    ABS(CAST(NEWID() AS binary(6)) %999) + ABS(CAST(NEWID() AS binary(6)) %999) *.0001
from numbers
union all
select
    ABS(CAST(NEWID() AS binary(6)) %999) + ABS(CAST(NEWID() AS binary(6)) %999) *.0001
from numbers
go
insert into gd values ('start', sysutcdatetime())
go
select StatRoundTo = [dbo].[udf-Stat-Round-To](col,.125) into #udf from t
go
insert into gd values ('udf',sysutcdatetime())
go
select StatRoundTo into #tvf from t cross apply [dbo].[udtvf-Stat-Round-To](t.col,.125)
go
insert into gd values ('tvf',sysutcdatetime())
go
select StatRoundTo = [dbo].[udf-Stat-Round-To](col,.125) into #udf2 from t
go
insert into gd values ('udf2',sysutcdatetime())
go
select StatRoundTo into #tvf2 from t cross apply [dbo].[udtvf-Stat-Round-To](t.col,.125)
go
insert into gd values ('tvf2',sysutcdatetime())
go
select 
    o.what
  , started=convert(varchar(30),x.ended) 
  , ended=convert(varchar(30),o.ended)
  , DurationInMs=datediff(millisecond,x.ended,o.ended)
from gd o
  outer apply (select top 1 ended from gd i where i.ended < o.ended order by i.ended desc) as x
go

View schema
Execution time: 6,36 sec, rows selected: 5, rows affected: 200005, absolute service time: 7,85 sec