如何编写可以针对给定数据库链接执行的整洁的PL / sql存储过程？
它变得非常混乱,写这样的东西：
PROCEDURE my_proc(aDbLink IN VARCHAR2)
IS
BEGIN
EXECUTE IMMEDIATE '
SELECT mycolumn,anothercolumn
FROM MYTABLE@' || aDbLink || '
WHERE such-and-such...'
END
随着查询变大.
解决方法
避免使用动态sql的最简单方法是创建同义词.
CREATE OR REPLACE SYNONYM MyTableRemote FOR MyTable@database_link
然后,您的存储过程将简单地引用同义词MyTableRemote.然后,您可以使用单独的方法将数据库链接名称作为参数,并将所有同义词更改为指向数据库链接.
PROCEDURE replace_synonyms( p_db_link IN VARCHAR2 )
AS
BEGIN
-- Adjust the query to identify all the synonyms that you want to recreate
FOR syn IN (SELECT *
FROM user_synonyms
WHERE db_link IS NOT NULL)
LOOP
EXECUTE IMMEDIATE
'CREATE OR REPLACE SYNONYM ' || syn.synonym_name ||
' FOR ' || syn.table_owner || '.' || syn.table_name || '@' || p_db_link;
END LOOP;
END;
