将 postgresql 函数转换为 oracle

Question

I need to support postgresql and oracle in the product that I work in. When we install our db on oracle, we do not give privilege of "create type". So I am unsure as to how I can convert following two cases to oracle:

1. Function That returns array

    create or replace function get_array_of_integers(i_param int) returns integer[] as $body$ declare array_of_integers int[]; begin select case when i_param = 1 then array[1] when i_param = 2 then array[1, 2, 3, 4] when i_param = 3 then array[5, 6] else array[]::integer[] end into array_of_integers; return array_of_integers; end; $body$ language 'plpgsql' volatile cost 100;

Second case: function that accepts array of integers:

create or replace function some_function(params int[])
 ...

Answer 1

You could make use of Oracle's built-in collection type sys.odcinumberlist .

Your function is equivalent to.

CREATE OR REPLACE FUNCTION get_array_of_integers(i_param INT)
RETURN sys.odcinumberlist
AS
  array_of_integers sys.odcinumberlist := NEW sys.odcinumberlist() ; --Initialization
BEGIN
    IF i_param = 1 THEN
      array_of_integers.EXTEND(1); 
      array_of_integers(1) := 1;
    ELSIF i_param = 2 THEN
      array_of_integers.EXTEND(4);--appends 4 null elements to a collection
      array_of_integers(1) := 1; --assign elements
      array_of_integers(2) := 2;
      array_of_integers(3) := 3;
      array_of_integers(4) := 4;
    ELSIF i_param = 3 THEN
      array_of_integers.EXTEND(2);
      array_of_integers(1) := 5;
      array_of_integers(2) := 6;
    END IF;

   RETURN array_of_integers;
END;
/  

You may use TABLE function in your query to select from this table.

SQL> select * FROM TABLE(get_array_of_integers(2));

COLUMN_VALUE
------------
           1
           2
           3
           4

SQL> select * FROM TABLE(get_array_of_integers(0));

no rows selected

For Oracle 12.2 and above, you won't need TABLE function, you can directly select from your function.

select * FROM get_array_of_integers(3);

Second case could be something like this.

 CREATE OR REPLACE FUNCTION some_function( params sys.odcinumberlist )
 RETURN INTEGER
 AS
 BEGIN
   RETURN 1;
 END;
 /