一些好玩的现象：
1、谁说同一个用户下面不能有两个表是同名的，看看下面，O(∩_∩)O哈哈~：
[oracle@lunar ~]$ ss SQL*Plus: Release 11.2.0.3.0 Production on Sat Jan 3 14:17:47 2015 Copyright (c) 1982, 2011, Oracle. All rights reserved. Welcome Lunar's oracle world! Love you , baby ! Connected to: Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production With the Partitioning and Real Application Testing options ERROR: ORA-22303: type "SYS"."DBMSOUTPUT_LINESARRAY" not found ORA-00942: table or view does not exist ORA-06508: PL/SQL: could not find program unit being called: "SYS.DBMS_OUTPUT" ORA-06512: at line 1 Session altered. Elapsed: 00:00:00.02 SYS@lunarp>select owner,segment_name,HEADER_FILE,HEADER_BLOCK from dba_segments where SEGMENT_NAME='LUNAR_BOOTSTRAP'; OWNER SEGMENT_NAME HEADER_FILE HEADER_BLOCK ------------------------------ -------------------------------------------------- ----------- ------------ SYS LUNAR_BOOTSTRAP 1 520 SYS LUNAR_BOOTSTRAP 4 434 Elapsed: 00:00:00.20 SYS@lunarp>
2、再看下面，我的库没有引导表了，O(∩_∩)O哈哈~：
SYS@lunarp>select object_id,object_name from dba_objects where object_name='%BOOTSTRAP%'; no rows selected Elapsed: 00:00:00.15 SYS@lunarp>select owner,segment_name,HEADER_FILE,HEADER_BLOCK from dba_segments where SEGMENT_NAME='%BOOTSTRAP%'; no rows selected Elapsed: 00:00:00.15 SYS@lunarp>select owner,segment_name from dba_segments where SEGMENT_NAME like '%BOOTSTRAP%'; OWNER SEGMENT_NAME ------------------------------ --------------------------------------------------------------------------------- SYSMAN MGMT_RT_BOOTSTRAP_TIMES SYSMAN MGMT_RT_BOOTSTRAP_TIMES_PK Elapsed: 00:00:00.21 SYS@lunarp>
3、看这里，表名区分大小写了，你知道为什么么？——— O(∩_∩)O哈哈~：
SYS@lunarp>select dbms_rowid.rowid_relative_fno(rowid) file#,
2 dbms_rowid.rowid_block_number(rowid) blk#
3 from BOOTSTRAP$;
from BOOTSTRAP$
*
ERROR at line 3:
ORA-00942: table or view does not exist
Elapsed: 00:00:00.00
SYS@lunarp>select dbms_rowid.rowid_relative_fno(rowid) file#,
2 dbms_rowid.rowid_block_number(rowid) blk#
3 from bootstrap$;
FILE# BLK#
---------- ----------
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 521
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 522
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
1 523
60 rows selected.
Elapsed: 00:00:00.13
SYS@lunarp>
4、你知道这是为什么么？————很好猜，O(∩_∩)O哈哈~
SYS@lunarp>select owner,segment_name,HEADER_FILE,HEADER_BLOCK from dba_segments where SEGMENT_NAME='LUNAR_BOOTSTRAP';
OWNER SEGMENT_NAME HEADER_FILE HEADER_BLOCK
------------------------------ -------------------------------------------------- ----------- ------------
SYS LUNAR_BOOTSTRAP 1 520
SYS LUNAR_BOOTSTRAP 4 434
Elapsed: 00:00:00.15
SYS@lunarp>select obj#,name from obj$ where name like '%BOOTSTRAP%';
OBJ# NAME
---------- ------------------------------
16077 IP_BOOTSTRAP_PRIMARY_KEY
16078 IP_DIST_BOOTSTRAP_PRIMARY_KEY
15554 MGMT_RT_BOOTSTRAP_TIMES
16072 MGMT_RT_BOOTSTRAP_TIMES_PK
15563 MGMT_RT_DOMAIN_BOOTSTRAP
15566 MGMT_RT_DOMAIN_DIST_BOOTSTRAP
16075 DOMAIN_BOOTSTRAP_PRIMARY_KEY
15569 MGMT_RT_IP_BOOTSTRAP
15572 MGMT_RT_IP_DIST_BOOTSTRAP
15557 MGMT_RT_URL_BOOTSTRAP
15560 MGMT_RT_URL_DIST_BOOTSTRAP
16073 URL_BOOTSTRAP_PRIMARY_KEY
16074 URL_DIST_BOOTSTRAP_PRIMARY_KEY
13 rows selected.
Elapsed: 00:00:00.01
SYS@lunarp>
5、被删除的表名被占用了，不能重用，这是为什么？
这是整个玩耍过程中，最郁闷的问题了………………………………
SYS@lunarp>drop table lunar_bootstrap purge ;
Table dropped.
Elapsed: 00:00:01.19
SYS@lunarp>create table lunar_bootstrap tablespace system as select * from bootstrap$ ;
create table lunar_bootstrap tablespace system as select * from bootstrap$
*
ERROR at line 1:
ORA-00955: name is already used by an existing object
Elapsed: 00:00:00.06
SYS@lunarp>col segment_name for a30
SYS@lunarp>select owner,segment_name,segment_type,extent_id,file_id,block_id from DBA_EXTENTS where segment_name like 'BOOTSTRAP$';
no rows selected
Elapsed: 00:00:00.34
SYS@lunarp>select owner,segment_name,HEADER_FILE,HEADER_BLOCK from dba_segments where SEGMENT_NAME='%BOOTSTRAP%';
no rows selected
Elapsed: 00:00:00.09
SYS@lunarp>select owner,segment_name from dba_segments where SEGMENT_NAME like '%BOOTSTRAP%';
OWNER SEGMENT_NAME
------------------------------ ------------------------------
SYS LUNAR_BOOTSTRAP
SYSMAN MGMT_RT_BOOTSTRAP_TIMES
SYSMAN MGMT_RT_BOOTSTRAP_TIMES_PK
Elapsed: 00:00:00.13
SYS@lunarp>select object_id,object_name from dba_objects where object_name='%BOOTSTRAP%';
no rows selected
Elapsed: 00:00:00.14
SYS@lunarp>
好了，不玩了，还原回来了，O(∩_∩)O哈哈~：
SYS@lunarp>select owner,segment_name,HEADER_FILE,HEADER_BLOCK from dba_segments where SEGMENT_NAME='BOOTSTRAP$'; OWNER SEGMENT_NAME HEADER_FILE HEADER_BLOCK ------------------------------ --------------------------------------------------------------------------------- ----------- ------------ SYS BOOTSTRAP$ 1 520 Elapsed: 00:00:00.15 SYS@lunarp>select owner,segment_name,HEADER_FILE,HEADER_BLOCK from dba_segments where SEGMENT_NAME='LUNAR_BOOTSTRAP'; OWNER SEGMENT_NAME HEADER_FILE HEADER_BLOCK ------------------------------ --------------------------------------------------------------------------------- ----------- ------------ SYS LUNAR_BOOTSTRAP 4 434 Elapsed: 00:00:00.02 SYS@lunarp>
