甲骨文：从选定的字符串执行查询

Question

SELECT 'ALTER TABLE ' || uc.table_name || ' DROP CONSTRAINT ' || uc.constraint_name FROM user_constraints uc WHERE constraint_type = 'R'; 

回报即某些语句，我可以手动执行，如：

ALTER TABLE APPLICATIONUSERROLE DROP CONSTRAINT APP_APPUSERROLE_FK1      
ALTER TABLE APPLICATIONUSERROLE DROP CONSTRAINT USER_APPUSERROLE_FK1      
ALTER TABLE APPLICATIONUSERROLE DROP CONSTRAINT ROLE_APPUSERROLE_FK1 

我有什么做的，自动执行呢？

比如我想：

EXECUTE IMMEDIATE (SELECT 'ALTER TABLE ' || uc.table_name || ' DROP CONSTRAINT ' || uc.constraint_name FROM user_constraints uc WHERE constraint_type = 'R'); 

但那不工作的抛出一些错误。

在此先感谢。

Answer 1

begin 
    for i in (SELECT 'ALTER TABLE ' || uc.table_name || ' DROP CONSTRAINT ' || uc.constraint_name as sql_text FROM user_constraints uc WHERE constraint_type = 'R') 
    loop 
     execute immediate i.sql_text; 
    end loop; 
end;