oracle删除已存在的表的实例

原创
2016-06-07 17:56:02 1033浏览

查询系统表,判断表是否存在,存在则直接删除

Sql代码
代码如下:
select count(*) from user_objects where object_name=upper(p_table_name);
select count(*) from user_tables where table_name=upper(p_table_name);

create or replace procedure p_drop_table_if_exist_v1(
p_table_name in varchar2
) is
v_count number(10);
begin
select count(*)
into v_count
from user_objects
where object_name=upper(p_table_name);
if v_count > 0 then
execute immediate 'drop table ' || p_table_name || ' purge';
end if;
exception
when no_data_found then
begin
null;
end;
end;
/

create or replace procedure p_drop_table_if_exist_v2(
p_table_name in varchar2
) is
v_table_name varchar2(20);
begin
select table_name
into v_table_name
from user_tables
where table_name=upper(p_table_name);
if length(v_table_name)>0 then
execute immediate 'drop table ' || p_table_name || ' cascade constraints';
end if;

exception
when no_data_found then
begin
null;
end;
end;
/
声明:本文内容由网友自发贡献,版权归原作者所有,本站不承担相应法律责任。如您发现有涉嫌抄袭侵权的内容,请联系admin@php.cn核实处理。