Dump buffer Cache

1. Base content: ALTER SESSION SET EVENTS ' immediate trace name buffers level n ';     N Value Meaning: 1 dumps the buffer header only.     2 Dumps the data block on a level 1 basis.     3 The data block content is then dumped on a level 2 basis.     4 Dump buffer header and hash chain.     5 Dumps the data block and hash chain on a level 1 basis.     6 The data block contents and hash chain are then dumped on the level 2 basis.     8 Dumps buffer header and hash chain and users/waiters linked list.     9 The data block, hash chain, and users/waiters linked list are then dumped on the level 1 basis. 10 The data block contents, hash chain, and users/waiters List 2 are then dumped on the level 2. Refreshes the buffer cache alter system flush BUFFER_CACHE;3. The contents of the exported data block #确定表所 Corresponding OBJECT_ID select object_id from dba_objects where object_name= ' T01 ';object_id-------------517804. Read data into buffer cache select * from t01;5.dump out buffer cache ALTER SESSION SET EVENTS ' immediate    Trace name buffers Level 3 ';    Current trace file location: > Oradebug setmypid;. > Oradebug tracefile_name;6. Find the Block BH (000007FF087EECC8) corresponding to the table in the dump file by object_idfile#: 1 rdba:0x0040ed92 (1/60818) class:1ba:000007ff08636000 set:3 blksize:8192 bsi:0 set-flg:2 pwbcnt:0 dbwrid:0obj:51780 objn:51780 tsn:0 afn:1 Hash: [9bf53d8,feee108] LRU: [97e7a88,57f7108] CKPTQ: [null] FILEQ: [null] OBJQ: [97E7AF8,E3D6DD8 ] st:xcurrent md:null tch:4 flags:only_sequential_access lrba: [0x0.0.0] HSCN: [0XFFFF.FFFFFFFF] HSUB:      [65535] buffer tsn:0 rdba:0x0040ed92 (1/60818) scn:0x0000.000a213e seq:0x04 flg:0x06 tail:0x213e0604 frmt:0x02 chkval:0xf9a7 Type:0x06=trans Data Hex dump of block:st=0, typ_found=1 .... data_block_d         Ump,data header at 0x44d005c =============== tsiz:0x1fa0 hsiz:0x1a pbl:0x044d005c bdba:0x0040ed92 76543210 flag=--------ntab=1 nrow=4 frre=3 fsbo=0x1a fseo=0x1e42 avsp=0x1f09 tosp=0x1f09 0x    E:pti[0] nrow=4 offs=0 0x12:pri[0] offs=0x1eb2 0x14:pri[1] offs=0x1ea6 0x16:pri[2] Offs=0x1e42  0X18:PRI[3] sfll=-1 block_row_dump:tab 0, row 0, @0x1eb2 tl:13 fb:--h-fl--lb:0x1 cc:2 col 0: [2] C1, col 1: [6] 6F 6c 0, row 1, @0x1ea6 tl:12 fb:--h-fl--lb:0x1 cc:2 col 0: [2] C1 col 1: [5] 6d  6c tab 0, row 2, @0x1e42 tl:100 fb:--h-fl--lb:0x1 cc:2 col 0: [2] C1 col 1: [6d] 6c 6f, 6c, 6d, 6c, 6f 6c, all-in-6d, 6c--------+----6f 6c------6d 6c 6d, 6c, 6f, all-in-6c, 6d, 6c, 6f, 6c, all, 6d, 6c, 6f, 6c 6c 6f, 6c, 6d, and 6c related fields brief description: |-------obj:51780 means object_id| |     The-------class represents the type of data block corresponding to the buffer header, and the exact value corresponds to the meaning: |1=data Block;|    2=sort block;| 3=save undo Block;|4=segment header;|    5=save undo Header;|    6=free list;|    7=extent map;|    8=1st level bmb;|    9=2nd level bmb;|    10=3rd level bmb;|    11=bitmap block;|    12=bitmap Index block;|    13=unused;|    14=undo header;| 15=undo block. | |    -------rdba:0x0040ed92 (1/60818) indicates that the object corresponds to a data block on a disk data file with address 1th file, 60818 blocks |    #确定表所在文件及数据块 |        Select |        rowid,|        DBMS_ROWID.ROWID_RELATIVE_FNO (ROWID) rel_fno,--File id|        Dbms_rowid.rowid_block_number (ROWID) block_no,--block number|        Dbms_rowid.rowid_row_number (ROWID) row_no,|    id|    From t01;| |    ROWID rel_fno block_no row_no id|    ------------------ ---------- ---------- ---------- ----------|    AAAMPEAABAAAO2SAAA 1 60818 0 0|    Aaampeaabaaao2saab 1 60818 1 1| AAAMPEAABAAAO2SAAC 1 60818 2 1

Reference blog:http://blog.csdn.net/orion61/article/details/8515340

Dump buffer Cache