返回兩個單獨的表PL/SQL

Question

我想通過兩個獨立的表來搜索特定值的COUNT並從一個函數返回它的數量的總和。

FUNCTION check_parts 
    (p_partno   IN VARCHAR2) 
    RETURN NUMBER 
    IS 
    out_exists NUMBER; 
    sub_exists NUMBER; 
    BEGIN 

    SELECT COUNT(*) INTO out_exists 
    FROM outline_pn op 
    WHERE op.outline_pn = p_partno 
    UNION ALL 
    SELECT COUNT(*) 
    FROM sub_pn sp 
    WHERE sp.sub_assy_pn = p_partno; 
--  SELECT (SELECT COUNT(*) AS out_exists 
--    FROM outline_pn op 
--    WHERE op.outline_pn = p_partno) AS out_exists, 
--    (SELECT COUNT(*) AS sub_exists 
--    FROM sub_pn sp 
--    WHERE sp.sub_assy_pn = p_partno) AS sub_exists 


     RETURN (out_exists + sub_exists); 
    END check_parts; 

起初我還天真地以爲兩個獨立COUNT(*)查詢會工作......沒有。

如何總結兩個獨立COUNT查詢的值，並返回結果？

任何幫助表示讚賞。

Answer 1

如果你仍然想擁有它在一個查詢，這裏是

create FUNCTION check_parts 
    (p_partno   IN VARCHAR2) 
    RETURN NUMBER 
    IS 
    sum_exists NUMBER; 
    BEGIN 

    select count(1) into sum_exists from (
    SELECT outline_pn 
    FROM outline_pn op 
    WHERE op.outline_pn = p_partno 
    UNION ALL 
    SELECT sub_assy_pn 
    FROM sub_pn sp 
    WHERE sp.sub_assy_pn = p_partno); 


     RETURN (sum_exists); 
    END check_parts; 

Answer 2

我沒有找到一個理由不使用兩個單獨的查詢。然後你可以返回兩者的總和。你可以簡單地寫這樣的事：

FUNCTION check_parts 
(p_partno   IN VARCHAR2) 
RETURN NUMBER 
IS 
out_exists NUMBER; 
sub_exists NUMBER; 
BEGIN 

SELECT COUNT(*) INTO out_exists 
FROM outline_pn op 
WHERE op.outline_pn = p_partno; 

SELECT COUNT(*) INTO sub_exits 
FROM sub_pn sp 
WHERE sp.sub_assy_pn = p_partno; 


RETURN (out_exists + sub_exists); 
END check_parts;