利用Oracle的enable validate约束进行数据检查

1创建原始表及数据

SQL> create table t1(id number, name varchar2(20));

Table created

SQL> insert into t1 values(1,'A');

1 row inserted

SQL> insert into t1 values(1,'B');

1 row inserted

SQL> insert into t1 values(2,'C');

1 row inserted

SQL> insert into t1 values(3,'D');

1 row inserted

SQL> insert into t1 values(3,'E');

1 row inserted

SQL> insert into t1 values(4,'F');

1 row inserted

SQL> commit;

Commit complete

2在表上创建enable novalidate主键

SQL> alter table t1 add constraint pk_t1 primary key(id) enable novalidate;

Table altered

3尝试将约束状态更改为 enable validate，却发现原有数据有问题

SQL> alter table t1 enable validate constraint pk_t1;

alter table t1 enable validate constraint pk_t1

ORA-02437:无法验证 (MYHR.PK_T1) -违反主键

4找出违反约束的数据，这里采用Exceptions表保存异常数据

SQL> @%ORACLE_HOME%RDBMS/ADMIN/utlexpt1.sql;

Table created

SQL> alter table t1 enable validate constraint pk_t1 exceptions into exceptions;

alter table t1 enable validate constraint pk_t1 exceptions into exceptions

ORA-02437:无法验证 (MYHR.PK_T1) -违反主键

5根据异常表，找出对应源表中的异常数据

SQL> select id, name from t1 where rowid in(select row_id from exceptions);

       ID NAME

---------- --------------------

        1 A

        1 B

        3 D

        3 E

6修正异常数据后，将索引生效