Oracle: split function result into multiple columns - oracle

Question

I have a package in oracle. In the package i have a procedure which performs an (insert into ..select.. ) statement
which is like this:
insert into some_table(col1 , col2 , col3, col4)
select col1 , col2, my_func(col3) as new_col3 , col4
from some_other_table
my_func(col3) does some logic to return a value.
now i need to to return two values instead of one, using the same logic.
i can simply write another function to do the same logic and return the second value, but that would be expensive because the function selects from a large history table.
i can't do a join with the history table because the function doesn't perform a simple select.
is there a way to get two columns by calling this function only once?

Answer 1

Create an OBJECT type with two attributes and return that from your function. Something like:
SQL Fiddle
Oracle 11g R2 Schema Setup:
CREATE TYPE my_func_type IS OBJECT(
value1 NUMBER,
value2 VARCHAR2(4000)
);
/
CREATE FUNCTION my_func
RETURN my_func_type
IS
value my_func_type;
BEGIN
value := my_func_type( 42, 'The Meaning of Life, The Universe and Everything' );
RETURN value;
END;
/
CREATE TABLE table1 (col1, col2, col5 ) AS
SELECT 1, 2, 5 FROM DUAL
/
Query 1:
SELECT col1,
col2,
t.my_func_value.value1 AS col3,
t.my_func_value.value2 AS col4,
col5
FROM (
SELECT col1,
col2,
my_func() AS my_func_value,
col5
FROM table1
) t
Results:
| COL1 | COL2 | COL3 | COL4 | COL5 |
|------|------|------|--------------------------------------------------|------|
| 1 | 2 | 42 | The Meaning of Life, The Universe and Everything | 5 |