oracle数据库如何清空所有表数据？
方法：
1，删除所有外键约束
2，drop表
3，添加外键约束
以下代码使用powerdesign生成。
例子：
复制代码 代码示例:
alter table Da_pic
drop constraint FK_DA_PIC_REFERENCE_DA_PICSU;
drop table Da_pic cascade constraints;
drop table Da_picsubject cascade constraints;
/*==============================================================*/
/* Table: Da_pic */
/*==============================================================*/
create table Da_pic (
ID VARCHAR2(200) not null,
no VARCHAR2(200),
subjiectid VARCHAR2(200),
Name VARCHAR2(400),
UploadTime DATE,
UserId VARCHAR2(200),
picdate DATE,
place VARCHAR2(200),
people VARCHAR2(200),
event VARCHAR2(200),
background VARCHAR2(200),
cameramen VARCHAR2(200),
serial INTEGER,
IsEffect VARCHAR2(200),
constraint PK_DA_PIC primary key (ID)
);
/*==============================================================*/
/* Table: Da_picsubject */
/*==============================================================*/
create table Da_picsubject (
ID VARCHAR2(200) not null,
no VARCHAR2(200),
title VARCHAR2(200),
year VARCHAR2(200),
type VARCHAR2(200),
gdtime DATE,
iseffect VARCHAR2(200),
seiral INTEGER,
constraint PK_DA_PICSUBJECT primary key (ID)
);
alter table Da_pic
add constraint FK_DA_PIC_REFERENCE_DA_PICSU foreign key (subjiectid)
references Da_picsubject (ID);
