八、闪回表emp
[html]
gyj@OCM> flashback table emp to before drop;
Flashback complete.
九、查回收站，已没信息，说明表和唯一索引（主键约束）都被闪回了，但外键没有被闪回（失去了外键的制约），如下操作。
[html]
gyj@OCM> select OBJECT_NAME,ORIGINAL_NAME,OPERATION,TYPE ,DROPTIME from recyclebin;
no rows selected
gyj@OCM> SELECT EMPNO,ENAME,DEPTNO FROM emp;
EMPNO ENAME DEPTNO
---------- ---------- ----------
1 KING 10
2 HARI 20
gyj@OCM> col index_name for a50
gyj@OCM> select index_name from user_indexes where table_name='EMP';
INDEX_NAME
--------------------------------------------------
BIN$5LNox53pT0PgQ4rZqMD+/Q==$0
gyj@OCM> col CONSTRAINT_NAME for a40
gyj@OCM> col index_name for a40
gyj@OCM> select CONSTRAINT_NAME,R_CONSTRAINT_NAME,TABLE_NAME,INDEX_NAME,CONSTRAINT_TYPE,STATUS
2 from user_constraints where table_name
3 in('EMP','DEPT');
CONSTRAINT_NAME R_CONSTRAI TABLE_NAME INDEX_NAME C STATUS
---------------------------------------- ---------- ---------- ---------------------------------------- - --------
PK_DEPT DEPT PK_DEPT P ENABLED
BIN$5LNox53oT0PgQ4rZqMD+/Q==$0 EMP BIN$5LNox53pT0PgQ4rZqMD+/Q==$0 P ENABLED
十、插入两条数据，第一次插入报错(emp中已存在empno为2的员工了，empno是主键)，第二次插入成功。
[html]
gyj@OCM> INSERT INTO emp(EMPNO,ENAME,DEPTNO) values(2,'COTT',10);
INSERT INTO emp(EMPNO,ENAME,DEPTNO) values(2,'COTT',10)
*
ERROR at line 1:
ORA-00001: unique constraint (GYJ.BIN$5LNox53oT0PgQ4rZqMD+/Q==$0) violated
gyj@OCM> INSERT INTO emp(EMPNO,ENAME,DEPTNO) values(3,'ING',55);
1 row created.
gyj@OCM> SELECT EMPNO,ENAME,DEPTNO FROM emp;
EMPNO ENAME DEPTNO
---------- ---------- ----------
1 KING 10
2 HARI 20
3 ING 55
十一、闪回索引和约束的名称还是：BIN$5LNox53pT0PgQ4rZqMD+/Q==$0和BIN$5LNox53oT0PgQ4rZqMD+/Q==$0，最好修改索引和约束，如下操作：
[html]
gyj@OCM> ALTER INDEX "BIN$5LNox53pT0PgQ4rZqMD+/Q==$0" RENAME TO PK_EMP;
Index altered.
gyj@OCM> ALTER TABLE EMP RENAME CONSTRAINT "BIN$5LNox53oT0PgQ4rZqMD+/Q==$0" TO PK_EMP;
Table altered.
gyj@OCM> select CONSTRAINT_NAME,R_CONSTRAINT_NAME,TABLE_NAME,INDEX_NAME,CONSTRAINT_TYPE,STATUS
2 from user_constraints where table_name
3 in('EMP','DEPT');
CONSTRAINT_NAME R_CONSTRAI TABLE_NAME INDEX_NAME C STATUS
---------------------------------------- ---------- ---------- ---------------------------------------- - --------
PK_DEPT DEPT PK_DEPT P ENABLED
PK_EMP EMP PK_EMP P ENABLED
gyj@OCM> select index_name from user_indexes where table_name='EMP';
INDEX_NAME
----------------------------------------
PK_EMP
呵呵，这样插入记录时报错就能看到正常的约束名称了。
[html]
gyj@OCM> INSERT INTO emp(EMPNO,ENAME,DEPTNO) values(2,'COTT',10);
INSERT INTO emp(EMPNO,ENAME,DEPTNO) values(2,'COTT',10)
*
ERROR at line 1:
ORA-00001: unique constraint (GY