oracle将sql语句写成存储过程

想要把原sql语句写成存储过程，这样以后就直接调用存储过程来执行这一段语句了
求大神帮忙看看我写的是否正确，谢谢
原sql语句：
TRUNCATE TABLE tab1;
INSERT tab1
SELECT s.storecode,s.category,nvl(curr.vol,0)/s.avg_vol - 1 AS growth
FROM
(
SELECT periodcode,storecode,CATEGORY,vol FROM tab2 WHERE periodcode = &periodcode) curr,
(SELECT storecode,category,AVG(vol) avg_vol FROM tab2

GROUP BY storecode,CATEGORY HAVING AVG(vol) > 0) s
WHERE curr.storecode(+) = aveg.storecode
AND curr.category(+) = s.category

打包为存储过程：
create or replace procedure p_tab1
AS
BEGIN
TRUNCATE TABLE tab1;
INSERT tab1
SELECT s.storecode,s.category,nvl(curr.vol,0)/s.avg_vol - 1 AS growth
FROM
(
SELECT periodcode,storecode,CATEGORY,vol FROM tab2 WHERE periodcode = &periodcode) curr,
(SELECT storecode,category,AVG(vol) avg_vol FROM tab2

GROUP BY storecode,CATEGORY HAVING AVG(vol) > 0) s
WHERE curr.storecode(+) = aveg.storecode
AND curr.category(+) = s.category

COMMIT;
END;

不太明白你的问题，你是要实现什么功能

你那条truncate语句是ddl语句,不能直接那么写.
改成

execute immediate 'TRUNCATE TABLE tab1';