【oracle】rowid转换rdba,rdba转换为file#block#

--数据的存储属性rowid

--数据文件file#

--数据库对象obj#

--数据块号：block_no#

--表中行号

--物理rowid和逻辑rowid

--索引使用逻辑rowid

--其他类型使用物理rowid

--rowid伪列

select rowid,id,time from rangetable;

--因为rowid唯一标示一条记录，所以索引存储rowid值；通过索引中，找到rowid；

--新的base64编码。32bit obj#,10bit rfile#,22bit block#,16bit row#

--因此每个表空间最大1022个文件，每个数据文件最大4M=4000个block

--每个block中的行数最大65536行；

--通过dbms_rowid来转换rowid的信息

create or replace function get_rowid(l_rowid in varchar2)

return varchar2

is

ls_my_rowid varchar2(200);

rowid_type number;

object_number number;

relative_fno number;

block_number number;

row_number number;

begin

dbms_rowid.rowid_info(l_rowid,rowid_type,object_number,relative_fno,block_number,row_number);

ls_my_rowid:=‘Object# is :‘

||to_char(object_number)||chr(10)||

‘relative_fno is :‘

||to_char(relative_fno)||chr(10)||

‘block_number is :‘

||to_char(block_number)||chr(10)||

‘row number is :‘

||to_char(row_number)||chr(10);

return ls_my_rowid;

end;

select rowid,a.* from dept a;

alter session set events ‘immediate trace name FILE_HDRS level 10‘

--查看udummp文件dba地址

RETURN VARCHAR2

IS

l_str   VARCHAR2 (255) DEFAULT NULL;

l_fno   VARCHAR2 (15);

l_bno   VARCHAR2 (15);

BEGIN

l_fno :=

DBMS_UTILITY.data_block_address_file (TO_NUMBER(LTRIM (p_dba, ‘0x‘), ‘xxxxxxxx‘));

l_bno :=

DBMS_UTILITY.data_block_address_block (TO_NUMBER (LTRIM (p_dba, ‘0x‘), ‘xxxxxxxx‘));

l_str :=

‘datafile# is:‘

|| l_fno

|| CHR (10)

|| ‘datablock is:‘

|| l_bno

|| CHR (10)

|| ‘dump command:alter system dump datafile ‘

|| l_fno

|| ‘ block ‘

|| l_bno

|| ‘;‘;

RETURN l_str;

END;