zoukankan      html  css  js  c++  java
  • [20171206]rman与truncate2.txt

    [20171206]rman与truncate2.txt

    --//上午测试发现truncate的表在做rman备份时还要做8个extents的备份.
    --//不知道自己的猜测是否正确,选择一个使用UNIFORM SIZE 的表空间测试看看.

    1.环境:
    SCOTT@book> @ &r/ver1
    PORT_STRING                    VERSION        BANNER
    ------------------------------ -------------- --------------------------------------------------------------------------------
    x86_64/Linux 2.4.xx            11.2.0.4.0     Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production

    CREATE TABLESPACE T01 DATAFILE
      '/mnt/ramdisk/book/T01.dbf' SIZE 20M AUTOEXTEND OFF
    LOGGING
    EXTENT MANAGEMENT LOCAL UNIFORM SIZE 40K
    BLOCKSIZE 8K
    SEGMENT SPACE MANAGEMENT MANUAL
    FLASHBACK ON;

    create table t01 tablespace t01 as select rownum id ,to_char(rownum,'FM000000')||lpad('A',26,'A') name from dual connect by level<=2e5;

    SCOTT@book> truncate table t01 ;
    Table truncated.

    SCOTT@book> alter system checkpoint ;
    System altered.

    SCOTT@book> alter system checkpoint ;
    System altered.

    RMAN> backup datafile 7 format '/home/oracle/backup/T1z_%U';
    Starting backup at 2017-12-06 15:10:42
    using channel ORA_DISK_1
    channel ORA_DISK_1: starting full datafile backup set
    channel ORA_DISK_1: specifying datafile(s) in backup set
    input datafile file number=00007 name=/mnt/ramdisk/book/T01.dbf
    channel ORA_DISK_1: starting piece 1 at 2017-12-06 15:10:42
    channel ORA_DISK_1: finished piece 1 at 2017-12-06 15:10:43
    piece handle=/home/oracle/backup/T1z_hdslesji_1_1 tag=TAG20171206T151042 comment=NONE
    channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
    Finished backup at 2017-12-06 15:10:43


    $ strings -t d T1z_hdslesji_1_1 | grep 'AAAAA'|head -1
      83254 K 000174AAAAAAAAAAAAAAAAAAAAAAAAAA,
    $ strings -t d T1z_hdslesji_1_1 | grep 'AAAAA'|tail -1
     401369 B_ 006539AAAAAAAAAAAAAAAAAAAAAAAAAA/
    $ strings -t d T1z_hdslesji_1_1 | grep 'AAAAA'|wc
       6710   18083  295828

    SCOTT@book> drop table t01 purge ;
    Table dropped.

    SCOTT@book> create table t01 tablespace t01 as select rownum id ,to_char(rownum,'FM000000')||lpad('A',26,'A') name from dual connect by level<=2e5;
    Table created.

    SCOTT@book> column name format a32
    SCOTT@book> select rowid,t01.* from t01 where id in (174,6539,6710);
    ROWID                      ID NAME
    ------------------ ---------- --------------------------------
    AAAWMCAAHAAAAAJACt        174 000174AAAAAAAAAAAAAAAAAAAAAAAAAA
    AAAWMCAAHAAAAAvAAA       6539 006539AAAAAAAAAAAAAAAAAAAAAAAAAA
    AAAWMCAAHAAAAAvACr       6710 006710AAAAAAAAAAAAAAAAAAAAAAAAAA

    SCOTT@book> @ &r/rowid  AAAWMCAAHAAAAAJACt
        OBJECT       FILE      BLOCK        ROW ROWID_DBA            DBA   TEXT
    ---------- ---------- ---------- ---------- -------------------- ----- ----------------------------------------
         90882          7          9        173  0x1C00009           7,9   alter system dump datafile 7 block 9 ;

    SCOTT@book> @ &r/rowid  AAAWMCAAHAAAAAvAAA
        OBJECT       FILE      BLOCK        ROW ROWID_DBA            DBA   TEXT
    ---------- ---------- ---------- ---------- -------------------- ----- ----------------------------------------
         90882          7         47          0  0x1C0002F           7,47  alter system dump datafile 7 block 47 ;

    SCOTT@book> @ &r/rowid  AAAWMCAAHAAAAAvACr
        OBJECT       FILE      BLOCK        ROW ROWID_DBA            DBA   TEXT
    ---------- ---------- ---------- ---------- -------------------- ----- ----------------------------------------
         90882          7         47        171  0x1C0002F           7,47  alter system dump datafile 7 block 47 ;

    SCOTT@book> select * from (select * from dba_extents where segment_name='T01' order by EXTENT_ID) where rownum<=10;
    OWNER  SEGMENT_NAME SEGMENT_TYPE TABLESPACE_NAME EXTENT_ID FILE_ID BLOCK_ID BYTES BLOCKS RELATIVE_FNO
    ------ ------------ ------------ --------------- --------- ------- -------- ----- ------ ------------
    SCOTT  T01          TABLE        T01                     0       7        8 40960      5            7
    SCOTT  T01          TABLE        T01                     1       7       13 40960      5            7
    SCOTT  T01          TABLE        T01                     2       7       18 40960      5            7
    SCOTT  T01          TABLE        T01                     3       7       23 40960      5            7
    SCOTT  T01          TABLE        T01                     4       7       28 40960      5            7
    SCOTT  T01          TABLE        T01                     5       7       33 40960      5            7
    SCOTT  T01          TABLE        T01                     6       7       38 40960      5            7
    SCOTT  T01          TABLE        T01                     7       7       43 40960      5            7
    SCOTT  T01          TABLE        T01                     8       7       48 40960      5            7
    SCOTT  T01          TABLE        T01                     9       7       53 40960      5            7
    10 rows selected.

    --//确实是8个extents.

  • 相关阅读:
    C#,asp.net,命名空间名,类名,方法名的获得
    asp.net引用用户控件
    SQL数据是否存在(是否有数据)判断,表,存储过程是否存在
    asp:Button 事件,点击事件 html Button runat="sever"
    CSS图片最大大小限制
    asp.net 路径
    Js实现网站的重定向,Js转向网址,Js跳转
    ViewState 页面状态保留
    vs 附加到进程
    sql XML处理,sp_xml_preparedocument,openxml
  • 原文地址:https://www.cnblogs.com/lfree/p/7992856.html
Copyright © 2011-2022 走看看