标签：rlwrap ready 必须 account and policy banner 2.0 oracle
[20180914]oracle 12c 表 full_hash_value如何计算.txt
--//昨天在12c下看表full_hash_value与11g的full_hash_value不同,不过12c使用pdb,猜测跟PDB有关.
--//通过测试说明问题.
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
SCOTT@book> select owner,name,namespace,type,hash_value,full_hash_value from V$DB_OBJECT_CACHE where owner=‘SCOTT‘ and name=‘EMP‘;
OWNER NAME NAMESPACE TYPE HASH_VALUE FULL_HASH_VALUE
------ ---- --------------- ----- ---------- --------------------------------
SCOTT EMP TABLE/PROCEDURE TABLE 3800164305 684ea11e3eab602b778e1dd1e281e7d1
--//以上11g的结果.
$ echo -e -n "EMP.SCOTT\01\0\0\0" | md5sum |sed ‘s/ -//‘ | xxd -r -p | od -t x4 | sed -n -e ‘s/^0000000 //‘ -e ‘s/ //gp‘
684ea11e3eab602b778e1dd1e281e7d1
2.而在12c下:
SCOTT@test01p> @ ver1
PORT_STRING VERSION BANNER CON_ID
------------------------------ -------------- -------------------------------------------------------------------------------- ----------
IBMPC/WIN_NT64-9.1.0 12.1.0.1.0 Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production 0
SCOTT@test01p> select owner,name,namespace,type,hash_value,full_hash_value,con_id,con_name from V$DB_OBJECT_CACHE where owner=‘SCOTT‘ and name=‘EMP‘;
OWNER NAME NAMESPACE TYPE HASH_VALUE FULL_HASH_VALUE CON_ID CON_NAME
-------------------- -------------------- -------------------- -------------------- ---------- -------------------------------- ---------- --------------------
SCOTT EMP TABLE/PROCEDURE TABLE 1676251406 5675b61ea54d0cd0370c43ab63e9910e 3 TEST01P
--//对比前面可以发现FULL_HASH_VALUE不一样,也很容易猜测12c 的FULL_HASH_VALUE计算加入CON_NAME的内容.
D:\tools\rlwrap>D:\tools\linux\usr\local\wbin\echo -e -n "EMP.SCOTT.TEST01P\01\0\0\0" | md5sum |sed "s/ -//" | D:\tools\Vim\vim80\xxd -r -p | od -t x4 | sed -n -e "s/^0000000 //" -e "s/ //gp"
5675b61ea54d0cd0370c43ab63e9910e
--//OK,能对上.
--//注:windows要安装unxutil包.echo不能使用windows下的echo.必须使用ubxutil包的echo(该命令支持-n -e参数)
--//sed 命令格式要使用双引号.
--//我个人还使用vim自带的xxd.
--//可以发现12c计算表的full_hash_value是 计算table_name.owner_name.con_name\01\0\0\0的md5sum值.
3.从以上测试可以联想到的问题就是后面都是补"\01\0\0\0",为什么呢?
--//很容易联想到namespace
SYS@test> select distinct kglhdnsp,kglhdnsd,kglobtyd from x$kglob order by 1;
KGLHDNSP KGLHDNSD KGLOBTYD
-------- ------------------------------ -------------------
0 SQL AREA CURSOR
1 TABLE/PROCEDURE CURSOR
1 TABLE/PROCEDURE FUNCTION
1 TABLE/PROCEDURE LIBRARY
1 TABLE/PROCEDURE OPERATOR
1 TABLE/PROCEDURE PACKAGE
1 TABLE/PROCEDURE PROCEDURE
1 TABLE/PROCEDURE SCHEDULER CLASS
1 TABLE/PROCEDURE SCHEDULER JOB
1 TABLE/PROCEDURE SCHEDULER PROGRAM
1 TABLE/PROCEDURE SCHEDULER SCHEDULE
1 TABLE/PROCEDURE SCHEDULER WINDOW
1 TABLE/PROCEDURE SEQUENCE
1 TABLE/PROCEDURE SYNONYM
1 TABLE/PROCEDURE TABLE
1 TABLE/PROCEDURE TYPE
1 TABLE/PROCEDURE VIEW
2 BODY CURSOR
2 BODY PACKAGE BODY
3 TRIGGER TRIGGER
4 INDEX INDEX
5 CLUSTER CLUSTER
5 CLUSTER CURSOR
10 QUEUE QUEUE
18 PUB SUB INTERNAL INFORMATION PUB SUB INTERNAL INFORMATION
23 RULESET RULESET
24 RESOURCE MANAGER RESOURCE MANAGER CONSUMER GROUP
24 RESOURCE MANAGER RESOURCE MANAGER PLAN
28 SUBSCRIPTION SUBSCRIPTION
38 RULE EVALUATION CONTEXT RULE EVALUATION CONTEXT
45 MULTI-VERSION OBJECT FOR TABLE CURSOR
45 MULTI-VERSION OBJECT FOR TABLE MULTI-VERSIONED OBJECT
48 MULTI-VERSION OBJECT FOR INDEX CURSOR
48 MULTI-VERSION OBJECT FOR INDEX MULTI-VERSIONED OBJECT
51 SCHEDULER GLOBAL ATTRIBUTE CURSOR
51 SCHEDULER GLOBAL ATTRIBUTE SCHEDULER GLOBAL ATTRIBUTE
52 RESOURCE MANAGER CDB RESOURCE MANAGER CDB PLAN
64 EDITION EDITION
69 DBLINK CURSOR
72 OBJECT ID OBJECT ID
73 SCHEMA CURSOR
73 SCHEMA NONE
74 DBINSTANCE CURSOR
75 SQL AREA STATS CURSOR STATS
79 ACCOUNT_STATUS NONE
82 SQL AREA BUILD CURSOR
88 PDB CURSOR
88 PDB PDB
93 AUDIT POLICY AUDIT POLICY
103 OPTIMIZER FINDING Optimizer Finding
104 OPTIMIZER DIRECTIVE OWNER CURSOR
104 OPTIMIZER DIRECTIVE OWNER Optimizer Directive Owner
113 GTT SESSION PRIVATE STATS CURSOR
125 PDBOPER CURSOR
54 rows selected.
--//比如你就不能建立emp的sequence.
SCOTT@test01p> create sequence emp cache 100;
create sequence emp cache 100
*
ERROR at line 1:
ORA-00955: name is already used by an existing object
4.SQL语句的full_hash_value(sql_id)计算还是和以前一样计算 sql文本\0(不包括分号) md5sum值.
--//这样带来一个问题,就是如果不同pdb下的语句如果一样,由于文本内容一样,这样计算的sql_id一样,导致出现大量子光标.
[20180914]oracle 12c 表 full_hash_value如何计算.txt
标签：rlwrap ready 必须 account and policy banner 2.0 oracle
原文地址：https://www.cnblogs.com/lfree/p/9649165.html
