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20:42:14 SQL> select user#,name from user$;

     USER# NAME

---------- ------------------------------          0 SYS ......         96 JYC         97 TEST

88 rows selected.

20:44:36 SQL> update user$ set name='JYC' where user#=97;

update user$ set name='JYC' where user#=97 * ERROR at line 1: ORA-00001: unique constraint (SYS.I_USER1) violated

20:45:11 SQL> update user$ set name='JYC1' where user#=97;

1 row updated.

20:45:28 SQL> update user$ set name='TEST' where user#=96;

1 row updated.

20:45:38 SQL> update user$ set name='JYC' where user#=97;

1 row updated.

20:45:47 SQL> commit;

Commit complete.

20:45:50 SQL> select user#,name from user$;

     USER# NAME

---------- ------------------------------          0 SYS

......

        83 SCOTT

        96 TEST         97 JYC

88 rows selected.

20:45:57 SQL> alter system checkpoint;

System altered.

20:46:05 SQL> alter system flush shared_pool;

System altered.

20:46:15 SQL> conn jyc/jyc

ERROR: ORA-01017: invalid username/password; logon denied

Warning: You are no longer connected to ORACLE. 20:46:33 SQL> conn jyc/test Connected. 20:46:38 SQL> conn test/jyc Connected. 20:46:43 SQL> conn /as sysdba Connected.

20:46:56 SQL> alter user jyc identified by jyc;

User altered.

20:47:01 SQL> alter user test identified by test;

User altered.

20:47:07 SQL> select count(*) from jyc.a;

  COUNT(*)

----------        496

20:47:22 SQL> select count(*) from jyc.b;

  COUNT(*)

----------         64

20:47:25 SQL> select count(*) from test.b;

  COUNT(*)

----------          1

20:47:28 SQL> select count(*) from test.a;

  COUNT(*)

----------         31

20:47:30 SQL> shutdown immediate

Database closed. Database dismounted. ORACLE instance shut down. 20:47:55 SQL> startup ORACLE instance started.

Total System Global Area 2455228416 bytes

Fixed Size                  2255712 bytes Variable Size             654312608 bytes Database Buffers         1778384896 bytes Redo Buffers               20275200 bytes Database mounted. Database opened. 20:48:02 SQL> select count(*) from jyc.a;

  COUNT(*)

----------        496

20:48:10 SQL> select count(*) from jyc.b;

  COUNT(*)

----------         64

20:48:13 SQL> conn jyc/jyc

Connected. 20:48:17 SQL> create table c as select * from a;

Table created.

20:48:26 SQL> select count(*) from c;

  COUNT(*)

----------        496

20:48:32 SQL> exit

Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production With the Partitioning, OLAP, Data Mining and Real Application Testing options [oracle@saperp ~]$ 

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