我们平时通过report schema看到的是当前数据库的定义信息，
如果使用 recovery catalog的情况下，我们可以看到数据库以前的数据结构的信息
比如：
1.增加表空间前的情况：
[oracle@dbserver ~]$ rman target / catalog rman/rman@192.168.133.1:1521/orcl
Recovery Manager: Release 11.2.0.4.0 - Production on Wed Aug 29 11:41:49 2018
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
connected to target database: SZTECH1 (DBID=3253410194)
connected to recovery catalog database
RMAN> report schema;
Report of database schema for database with db_unique_name SZTECH1
List of Permanent Datafiles
===========================
File Size(MB) Tablespace RB segs Datafile Name
---- -------- -------------------- ------- ------------------------
1 740 SYSTEM YES /u01/app/oracle/oradata/sztech1/system01.dbf
2 570 SYSAUX NO /u01/app/oracle/oradata/sztech1/sysaux01.dbf
3 105 UNDOTBS1 YES /u01/app/oracle/oradata/sztech1/undotbs01.dbf
4 303 USERS NO /u01/app/oracle/oradata/sztech1/user01.dbf
5 330 EXAMPLE NO /u01/app/oracle/oradata/sztech1/example01.dbf
List of Temporary Files
=======================
File Size(MB) Tablespace Maxsize(MB) Tempfile Name
---- -------- -------------------- ----------- --------------------
1 29 TEMP 32767 /u01/app/oracle/oradata/sztech1/temp01.dbf
2.加一个表空间，ts_test
可以记录这个时间为：2018-08-29 12:08:47
[oracle@dbserver ~]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.4.0 Production on Wed Aug 29 12:08:47 2018
Copyright (c) 1982, 2013, Oracle. All rights reserved.
SQL> conn / as sysdba
Connected.
SQL> create tablespace ts_test datafile '/u01/app/oracle/oradata/sztech1/ts_test01.dbf' size 10m;
Tablespace created.
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
3.使用report schema,看到当前的表空间情况，包含新增加的表空间ts_test
[oracle@dbserver ~]$ rman target / catalog rman/rman@192.168.133.1:1521/orcl
Recovery Manager: Release 11.2.0.4.0 - Production on Wed Aug 29 12:09:17 2018
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
connected to target database: SZTECH1 (DBID=3253410194)
connected to recovery catalog database
RMAN> report schema ;
Report of database schema for database with db_unique_name SZTECH1
List of Permanent Datafiles
===========================
File Size(MB) Tablespace RB segs Datafile Name
---- -------- -------------------- ------- ------------------------
1 740 SYSTEM YES /u01/app/oracle/oradata/sztech1/system01.dbf
2 570 SYSAUX NO /u01/app/oracle/oradata/sztech1/sysaux01.dbf
3 105 UNDOTBS1 YES /u01/app/oracle/oradata/sztech1/undotbs01.dbf
4 303 USERS NO /u01/app/oracle/oradata/sztech1/user01.dbf
5 330 EXAMPLE NO /u01/app/oracle/oradata/sztech1/example01.dbf
6 10 TS_TEST NO /u01/app/oracle/oradata/sztech1/ts_test01.dbf
List of Temporary Files
=======================
File Size(MB) Tablespace Maxsize(MB) Tempfile Name
---- -------- -------------------- ----------- --------------------
1 29 TEMP 32767 /u01/app/oracle/oradata/sztech1/temp01.dbf
4. 使用创建新表空间之前的时间查询：
RMAN> report schema at time "to_date('2018-08-29 12:08:47','yyyy-mm-dd hh24:mi:ss')";
Report of database schema for database with db_unique_name SZTECH1
List of Permanent Datafiles
===========================
File Size(MB) Tablespace RB segs Datafile Name
---- -------- -------------------- ------- ------------------------
1 740 SYSTEM YES /u01/app/oracle/oradata/sztech1/system01.dbf
2 570 SYSAUX NO /u01/app/oracle/oradata/sztech1/sysaux01.dbf
3 105 UNDOTBS1 YES /u01/app/oracle/oradata/sztech1/undotbs01.dbf
4 303 USERS NO /u01/app/oracle/oradata/sztech1/user01.dbf
5 330 EXAMPLE NO /u01/app/oracle/oradata/sztech1/example01.dbf
List of Temporary Files
=======================
File Size(MB) Tablespace Maxsize(MB) Tempfile Name
---- -------- -------------------- ----------- --------------------
1 29 TEMP 32767 /u01/app/oracle/oradata/sztech1/temp01.dbf
这个时候，我们发现，新表空间不见了。
5. 当然，这个功能只能使用了 recovery catalog的情况下，才可以 。
[oracle@dbserver ~]$ rman target /
Recovery Manager: Release 11.2.0.4.0 - Production on Wed Aug 29 12:37:12 2018
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
connected to target database: SZTECH1 (DBID=3253410194)
RMAN> report schema at time "to_date('2018-08-29 12:08:47','yyyy-mm-dd hh24:mi:ss')";
using target database control file instead of recovery catalog
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of report command at 08/29/2018 12:37:18
RMAN-06137: must have recovery catalog for REPORT SCHEMA AT TIME
