[SQL] Doubt about User-defined function.

[sathiya moorthy]

       I have doubt about user-defined function returns value  :

             *  why function returns( accepts  ) One attribute in the arguments of function/table, Otherwise it returns the whole record of the table. Function accept more than arguments .
                      *   Why it doesn`t return more than one arguments in the function (or) Attribute of that table.

            *    Its like same as C-language function, Because in C function returns one value (or) structure/array of characters.

            *   My question is, In psql user-defined function doesn`t returns more than one attribute. Is it possible (or) Not.

     Some examples :
            i)      create function com2(text,integer) returns text as ' select city.city from city,weather
                    where weather.city=$1 AND city.pop>$2' language sql;

                    Res : Return type of the function is Text, As well as it is one of the argument of function.
                              ( At the type of returning, why it doesn`t  also accepts integer ).            
          ii)      create function usrs_tab(text,integer) returns city as 'select city.city,city.pop,city.state from                                        city,weather  where weather.city=$1 AND city.pop>$2' language sql;

                   Res : Return one  record from City table  ( table contains city, pop, state only ).


                                                   Thanking you.

--
sathiyamoorthy