hi
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount
ORACLE instance started.
Total System Global Area 131142648 bytes
Fixed Size 451576 bytes
Variable Size 104857600 bytes
Database Buffers 25165824 bytes
Redo Buffers 667648 bytes
Database mounted.
SQL> alter session set sql_trace = true;
Session altered.
SQL> alter database open;
Database altered.
SQL>
(reference to the trace file )
>#1st
create table bootstrap$ ( line# number not null, obj#
number not null, sql_text varchar2(4000) not null) storage (initial
50K objno 56 extents (file 1 block 377))
>#2nd
select line#, sql_text
from
bootstrap$ where obj# != :1 --- the var should be -1
>#let's look at the bootstrap$
SQL> desc bootstrap$
Name Null? Type
----------------------------------------- -------- ----------------------------
LINE# NOT NULL NUMBER
OBJ# NOT NULL NUMBER
SQL_TEXT NOT NULL VARCHAR2(4000)
SQL>
SQL> select count(*) from bootstrap$;
57
SQL>
SQL> select obj#,sql_text from bootstrap$ where rownum<11;
-1
8.0.0.0.0
0
CREATE ROLLBACK SEGMENT SYSTEM STORAGE ( INITIAL 112K NEXT 1024K MINEXTENTS 1 M
AXEXTENTS 32765 OBJNO 0 EXTENTS (FILE 1 BLOCK 9))
8
CREATE CLUSTER C_FILE#_BLOCK#("TS#" NUMBER,"SEGFILE#" NUMBER,"SEGBLOCK#" NUMBER)
PCTFREE 10 PCTUSED 40 INITRANS 2 MAXTRANS 255 STORAGE ( INITIAL 24K NEXT 1024K
MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 OBJNO 8 EXTENTS (FILE 1 BLOCK
73)) SIZE 225
9
CREATE INDEX I_FILE#_BLOCK# ON CLUSTER C_FILE#_BLOCK# PCTFREE 10 INITRANS 2 MAXT
RANS 255 STORAGE ( INITIAL 64K NEXT 1024K MINEXTENTS 1 MAXEXTENTS 2147483645 PC
TINCREASE 0 OBJNO 9 EXTENTS (FILE 1 BLOCK 81))
14
CREATE TABLE SEG$("FILE#" NUMBER NOT NULL,"BLOCK#" NUMBER NOT NULL,"TYPE#" NUMBE
R NOT NULL,"TS#" NUMBER NOT NULL,"BLOCKS" NUMBER NOT NULL,"EXTENTS" NUMBER NOT N
ULL,"INIEXTS" NUMBER NOT NULL,"MINEXTS" NUMBER NOT NULL,"MAXEXTS" NUMBER NOT NUL
L,"EXTSIZE" NUMBER NOT NULL,"EXTPCT" NUMBER NOT NULL,"USER#" NUMBER NOT NULL,"LI
STS" NUMBER,"GROUPS" NUMBER,"BITMAPRANGES" NUMBER NOT NULL,"CACHEHINT" NUMBER NO
T NULL,"SCANHINT" NUMBER NOT NULL,"HWMINCR" NUMBER NOT NULL,"SPARE1" NUMBER,"SPA
RE2" NUMBER) STORAGE ( OBJNO 14 TABNO 2) CLUSTER C_FILE#_BLOCK#(TS#,FILE#,BLOCK
#)
5
CREATE TABLE CLU$("OBJ#" NUMBER NOT NULL,"DATAOBJ#" NUMBER,"TS#" NUMBER NOT NULL
,"FILE#" NUMBER NOT NULL,"BLOCK#" NUMBER NOT NULL,"COLS" NUMBER NOT NULL,"PCTFRE
E$" NUMBER NOT NULL,"PCTUSED$" NUMBER NOT NULL,"INITRANS" NUMBER NOT NULL,"MAXTR
ANS" NUMBER NOT NULL,"SIZE$" NUMBER,"HASHFUNC" VARCHAR2(30),"HASHKEYS" NUMBER,"F
UNC" NUMBER,"EXTIND" NUMBER,"FLAGS" NUMBER,"DEGREE" NUMBER,"INSTANCES" NUMBER,"A
VGCHN" NUMBER,"SPARE1" NUMBER,"SPARE2" NUMBER,"SPARE3" NUMBER,"SPARE4" NUMBER,"S
PARE5" VARCHAR2(1000),"SPARE6" VARCHAR2(1000),"SPARE7" DATE) STORAGE ( OBJNO 5
TABNO 2) CLUSTER C_OBJ#(OBJ#)
6
CREATE CLUSTER C_TS#("TS#" NUMBER) PCTFREE 10 PCTUSED 40 INITRANS 2 MAXTRANS 255
STORAGE ( INITIAL 64K NEXT 1024K MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREAS
E 0 OBJNO 6 EXTENTS (FILE 1 BLOCK 57))
7
CREATE INDEX I_TS# ON CLUSTER C_TS# PCTFREE 10 INITRANS 2 MAXTRANS 255 STORAGE (
INITIAL 64K NEXT 1024K MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 OBJNO
7 EXTENTS (FILE 1 BLOCK 65))
18
CREATE TABLE OBJ$("OBJ#" NUMBER NOT NULL,"DATAOBJ#" NUMBER,"OWNER#" NUMBER NOT N
ULL,"NAME" VARCHAR2(30) NOT NULL,"NAMESPACE" NUMBER NOT NULL,"SUBNAME" VARCHAR2(
30),"TYPE#" NUMBER NOT NULL,"CTIME" DATE NOT NULL,"MTIME" DATE NOT NULL,"STIME"
DATE NOT NULL,"STATUS" NUMBER NOT NULL,"REMOTEOWNER" VARCHAR2(30),"LINKNAME" VAR
CHAR2(128),"FLAGS" NUMBER,"OID$" RAW(16),"SPARE1" NUMBER,"SPARE2" NUMBER,"SPARE3
" NUMBER,"SPARE4" VARCHAR2(1000),"SPARE5" VARCHAR2(1000),"SPARE6" DATE) PCTFREE
10 PCTUSED 40 INITRANS 1 MAXTRANS 255 STORAGE ( INITIAL 16K NEXT 1024K MINEXTEN
TS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 OBJNO 18 EXTENTS (FILE 1 BLOCK 121))
36
CREATE UNIQUE INDEX I_OBJ1 ON OBJ$(OBJ#) PCTFREE 10 INITRANS 2 MAXTRANS 255 STOR
AGE ( INITIAL 64K NEXT 1024K MINEXTENTS 1 MAXEXTENTS 2147483645 PCTINCREASE 0 O
BJNO 36 EXTENTS (FILE 1 BLOCK 217))
10 rows selected.
SQL>
>#we can see that the bootstrap$ stored the DDL script for the system objects
>#let's check the trace content
CREATE ROLLBACK SEGMENT SYSTEM STORAGE ( INITIAL 112K NEXT 1024K MINEXTENTS
1 MAXEXTENTS 32765 OBJNO 0 EXTENTS (FILE 1 BLOCK 9))
>#here create a system rollback segment header at "file 1 block 9"(LMT ,not DMT)
>#go on
CREATE CLUSTER C_OBJ#("OBJ#" NUMBER) PCTFREE 5 PCTUSED 40 INITRANS 2 MAXTRANS
255 STORAGE ( INITIAL 136K NEXT 1024K MINEXTENTS 1 MAXEXTENTS 2147483645
PCTINCREASE 0 OBJNO 2 EXTENTS (FILE 1 BLOCK 25)) SIZE 800
># notice that "OBJNO 2 EXTENTS (FILE 1 BLOCK 25)) SIZE 800"
>#query
SQL> select file_id,block_id from dba_extents where segment_name = 'C_OBJ#';
1 25
1 33
1 41
1 3241
1 4441
1 4473
1 4489
1 4513
1 4529
1 4561
1 4585
1 4609
1 4641
1 4681
1 4753
1 4833
1 4873
1 12681
1 23689
1 26249
20 rows selected.
>#go on
CREATE INDEX I_OBJ# ON CLUSTER C_OBJ# PCTFREE 10 INITRANS 2 MAXTRANS 255
STORAGE ( INITIAL 64K NEXT 1024K MINEXTENTS 1 MAXEXTENTS 2147483645
PCTINCREASE 0 OBJNO 3 EXTENTS (FILE 1 BLOCK 49))
CREATE TABLE TAB$("OBJ#" NUMBER NOT NULL,"DATAOBJ#" NUMBER,"TS#" NUMBER NOT
NULL,"FILE#" NUMBER NOT NULL,"BLOCK#" NUMBER NOT NULL,"BOBJ#" NUMBER,"TAB#"
NUMBER,"COLS" NUMBER NOT NULL,"CLUCOLS" NUMBER,"PCTFREE$" NUMBER NOT NULL,
"PCTUSED$" NUMBER NOT NULL,"INITRANS" NUMBER NOT NULL,"MAXTRANS" NUMBER NOT
NULL,"FLAGS" NUMBER NOT NULL,"AUDIT$" VARCHAR2(38) NOT NULL,"ROWCNT" NUMBER,
"BLKCNT" NUMBER,"EMPCNT" NUMBER,"AVGSPC" NUMBER,"CHNCNT" NUMBER,"AVGRLN"
NUMBER,"AVGSPC_FLB" NUMBER,"FLBCNT" NUMBER,"ANALYZETIME" DATE,"SAMPLESIZE"
NUMBER,"DEGREE" NUMBER,"INSTANCES" NUMBER,"INTCOLS" NUMBER NOT NULL,
"KERNELCOLS" NUMBER NOT NULL,"PROPERTY" NUMBER NOT NULL,"TRIGFLAG" NUMBER,
"SPARE1" NUMBER,"SPARE2" NUMBER,"SPARE3" NUMBER,"SPARE4" VARCHAR2(1000),
"SPARE5" VARCHAR2(1000),"SPARE6" DATE) STORAGE ( OBJNO 4 TABNO 1) CLUSTER
C_OBJ#(OBJ#)
># from tab$ , notice that "STORAGE ( OBJNO 4 TABNO 1) CLUSTER C_OBJ#(OBJ#)"
># what are the "objno 4 tabno 1" ? we can look up the tab$ via "cluster
>C_OBJ#(OBJ#)"
SQL> select * from tab$ where obj# = 4 and tab# = 1;
OBJ# DATAOBJ# TS# FILE# BLOCK# BOBJ# TAB#
---------- ---------- ---------- ---------- ---------- ---------- ----------
COLS CLUCOLS PCTFREE$ PCTUSED$ INITRANS MAXTRANS FLAGS
---------- ---------- ---------- ---------- ---------- ---------- ----------
AUDIT$ ROWCNT BLKCNT EMPCNT
-------------------------------------- ---------- ---------- ----------
AVGSPC CHNCNT AVGRLN AVGSPC_FLB FLBCNT ANALYZETI SAMPLESIZE
---------- ---------- ---------- ---------- ---------- --------- ----------
DEGREE INSTANCES INTCOLS KERNELCOLS PROPERTY TRIGFLAG SPARE1
---------- ---------- ---------- ---------- ---------- ---------- ----------
SPARE2 SPARE3
---------- ----------
SPARE4
--------------------------------------------------------------------------------
SPARE5
--------------------------------------------------------------------------------
SPARE6
---------
4 2 0 1 25 2 1
37 1 0 0 0 0 17
-------------------------------- 921 428 83
2381 0 139 6368 7 11-AUG-03 921
37 37 1024 0 0
06-AUG-03
SQL>
># now we see that from here to DB complete open, all the objects storage
>come from fixed file# and block#
># so if these system block corrupted ,the DB can not open
one year ago , i thought that oracle can query much information via
the data dictionary tables/views
but , how to found the basic information . the data are stored in system but we
can query it on sql . user table's structure information come from DICT tables
, but how about the DICT table's structure information ?
so i do the test ,and find the egg ---- bootstrap$
the egg can hatch the c_obj$ and tab$ ...
i guess the bootstrap$'s structure or storage information are also stored in
the oracle code (like oracle.exe)
and when opening , oracle only create the structrue(include the storage
information) in the shared pool but do not create the segment in the system
tablespace . and , the "DDL" do not live in the shared pool,we can not query
it in v$sql/v$sqlarea .
Best regards
yahoo id: feng_chunpei
A new dba from china
-- Binary/unsupported file stripped by Ecartis --
-- Type: application/octet-stream
-- File: dbopen.txt
----------------------------------------------------------------
Please see the official ORACLE-L FAQ: http://www.orafaq.com
----------------------------------------------------------------
To unsubscribe send email to: oracle-l-request@xxxxxxxxxxxxx
put 'unsubscribe' in the subject line.
--
Archives are at //www.freelists.org/archives/oracle-l/
FAQ is at //www.freelists.org/help/fom-serve/cache/1.html
-----------------------------------------------------------------
