SQL> alter table t_user disable primary key cascade;

Table altered.

SQL> truncate table t_user;

Table truncated.

SQL> alter table t_user enable primary key;

Table altered.

把主键暂停后，外键也就失效了，一下语句查看失效的约束

select constraint_name,table_name,status from user_constraints where status='DISABLED';

构造使约束生效的脚本

SQL> select 'alter table '||table_name||' enable constraint '||constraint_name||';' from user_constraints where status='DISABLED';

SQL> alter table t_province_purview enable constraint fk_t_provin_relations_t_user;

Table altered.

ITPub博客

ORA-02266: unique/primary keys in table referenced by enabled foreign keys