create function using language SQL

Hi all,

As I was reading up on create function etc. while learning plpgsql, I seam to 
remember it stated that as well as plpgsql, that other languages are/will be 
available including using SQL as the language.  However, I cannot find the 
syntax to create a function in SQL.  Specifically, how you return the result.

As an example, how would I create a SQL function to match the plpgsql 
function below?


CREATE FUNCTION getteamno(int4) RETURNS varchar  AS '
DECLARE    unitno varchar;
BEGIN   select into unitno       tregion || ''/'' ||to_char(tnumber,''FM000'')       from teams       where tid = $1;
ifnot found then     raise exception ''Team % not found'',$1;     return '''';   end if;   return unitno;
 
END;
' LANGUAGE 'plpgsql';

-- 
Gary Stainburn
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