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  2006年12月8日

Question:
The restore command works fine, but while attempting the rolforward of the sql logs, it complains about database falling short on bufferpool,and then terminates the rollforward process. One close look at the db2diag.log file, I noticed that db2 tried to start the database with the hidden bufferpool. But, apparently, that hidden bufferpool was pretty small to rollforward the logs and bring it online.

I cannot reduce the bufferpool size as the database cannot be connected to.I cannot connect to the database as it is in rollforward pending state. I cannot rollforward the database, as it's not happy with the size of the *hidden* bufferpool and terminates.

Answer:

db2set DB2_OVERRIDE_BPF=50000

This will bring up all configured bufferpools using 50000 pages each. You
can choose a smaller/larger value that is suitable for your number of
bufferpools and available system memory. You can also configure each
bufferpool individually if you want

値: 正数のページ数
     OR
 <entry>[;<entry>...] (<entry>=<バッファー・プール ID>,<ページ数> )

There is sitiuation that above solution does not work.

				When you try to create a bufferpool or alter a bufferpool to a
very large size and there is not enough memory in the system
, DB2 may occupies all pagespace and overrall performance of
the system become slow and may get hang at last because no
pagespace is available. Then after you connect the database
next time, DB2 will do crash recovery and still try to
allocate memory for this big bufferpool and occupy all
pagespace again. when you specify DB2_OVERRIDE_BPF parameter
to override bufferpool size, it doesn't take effect in this
situation. This is becasue DB2_OVERRIDE_BPF only applies for
bufferpools that already exist at startup, and not to
bufferpools that are created during crash recovery or roll
forward. We will fix this problem and check DB2_OVERRIDE_BPF
registry when creating bufferpools during crash recovery or
roll forward. This problem only occurs in a 64 bit instance.

		

Local fix

				You can use db2iupdt -w 32 <INSTNAME> to update the instance to
a 32 bit instance, then you can connect to the database
succefully. After that, use db2iupdt -w 64 <INSTNAME> to update
the instance to 64 bit again. Please take a backup at this
point, so we don't have to roll forward through bufferpool
creation that fails if we need restore and roll forward
database.

		

Problem summary

				Users Affected:
All users using 64 bit instance
Problem Description:
When you try to create a bufferpool or alter a bufferpool to a
very large size and there is not enough memory in the system
, DB2 may occupies all pagespace and overrall performance
of the system become slow and may get hang at last
because no pagespace is available. Then after you connect the
database at next time, DB2 will do crash recovery and still try
to allocate
memory for this big bufferpool and occupy all pagespace again.
In this situation, when you specify DB2_OVERRIDE_BPF parameter
to override bufferpool size, it doesn't take effect in this
situation. This
is becasue DB2_OVERRIDE_BPF only applies for bufferpools that
already exist at startup, and not to bufferpools that are
created during crash recovery or roll forward. We will fix
this problem and check
DB2_OVERRIDE_BPF registry when creating bufferpools during crash
recovery or roll forward. This problem only occurs in 64 bit
instance.
Problem Summary:
This problem is caused by a misoperation, when you create or alt
er a bufferpool, the size is too large to allocated from OS and
cause overrall performance of the system is very slow and seems
hang. Another problem is that DB2_OVERRIDE_BPF registry only app
lies to bufferpools that already exists, and not bufferpools wil
l be created in crash recovery or roll forward. So DB2 will try
to create this big bufferpool again when doing crash recovery or
 roll forward. We will fix this problem and check DB2_OVERRIDE_B
PF registry in our crash recovery and roll forward code.

		

Problem conclusion

				
				
		

Temporary fix

				You can use db2iupdt -w 32 <INSTNAME> to update the instance to
a 32 bit instance, then you can connect to the database
succefully. After that, use db2iupdt -w 64 <INSTNAME> to update
the instance to 64 bit again. Please take a backup at this
point, so we don't have to roll forward through bufferpool
creation that fails if we need restore and roll
forward database.Please also notice that be careful when creati
ng bufferpool, don't specify a too large value.

		


posted @ 2007-03-15 15:21 MyJavaWorld 阅读(717) | 评论 (0)编辑 收藏

Change db2 password in db2 level

DB2 depends on operation system level authorization to control DB2 system access.

In some case, our db2 account only allows to connect to instance or database, but not log on the system. In other words, we are not able to use the account to get a shell on unix or logon locally on windows.

As usual, when we need to change db2 password, we take action on the system level because it's more frank. But in the case above that we can't get logon, we have to do it on db2 level. There are 2 ways.

  • Use the GUI tool DB2 Configuration Assistance
  • Use the command line tools DB2 CLP or CE

Using DB2 Configuration Assistance

Right click on a database name, then choose "Change password".

CA tool interface

Note: When more than one databases live in same system, we might share the same account in multi-database. Changing password for one of them will affect all databases in this system. In other words, we don't need to do the change on each database, we could choose any we have privileges on the system.

Limitation: We are not able to change our password in the case of that we are only allowed to attach to the node but not connect to any database, or we don't get the catalog information for any database in the node.

For this limitation, it works out with the 2nd way. 

Using DB2 CLP and CE

We could use CLP and CE to change password for databases and nodes that we connected or attached to.

  • Change by connecting to database
C:\> db2 connect to SAMPLE user TEST using OLDPWD new NEWPWD confirm NEWPWD
C:\> db2 connect to SAMPLE user TEST using OLDPWD change password
  • Change by attaching to node, this way works out for the limitation in Configuration Assistance
C:\> db2 attach to NODE user TEST using OLDPWD new NEWPWD confirm NEWPWD
C:\> db2 attach to NODE user TEST using OLDPWD change password


alter table xxx VOLATILE

valatile

  • a. 反复无常的,挥发性的

VOLATILE CARDINALITY or NOT VOLATILE CARDINALITY
Indicates to the optimizer whether or not the cardinality of table table-name can
vary significantly at run time. Volatility applies to the number of rows in the
table, not to the table itself. CARDINALITY is an optional keyword. The default
is NOT VOLATILE.

VOLATILE
Specifies that the cardinality of table table-name can vary significantly at
run time, from empty to large. To access the table, the optimizer will use
an index scan (rather than a table scan, regardless of the statistics) if that
index is index-only (all referenced columns are in the index), or that index
is able to apply a predicate in the index scan. The list prefetch access method
will not be used to access the table. If the table is a typed table, this option
is only supported on the root table of the typed table hierarchy (SQLSTATE 428DR).

NOT VOLATILE
Specifies that the cardinality of table-name is not volatile.
Access plans to this table will continue to be based on existing statistics and
on the current optimization level.

NOTE: The keyword could be specified within ALTER TABLE, but not CREATE TABLE.

 

Difference between Local and System Database Directory

DB2 automatically catalogs databases when they are created. It catalogs an entry
for the database in the local database directory and another entry in the system
database directory. If the database is created from a remote client (or a client which
is executing from a different instance on the same machine), an entry is also made
in the system database directory at the client instance.

Databases on the same node as the database manager instance are cataloged as
indirect entries. Databases on other nodes are cataloged as remote entries.

List DBs in Local Database Directory

$ db2 list db directory on /path_to_where_db_created 

List DBs in System Database Directory

$ db2 list db directory

 

Illustration of standard tables

Standard Tables Overview

Query the status for one specified tablespace?

As we know, we could issue following command to query status for all of tablespaces in current connected DB.

$ db2 list tablespaces show detail > /tmp/ts.list

Then find the status for the tablespaces we concerned.

Is there's a way to query the status for one specified tablespace?

My answer is No. 

  1. First, I don't find the related column defination in the table or view:
    • sysibm.systablespaces
    • syscat.tablespaces
  2. Second, I don't think DB2 stores the status flag within syscata tables. The reason is that once a tablespace comes into a special status, it will not be allowed changing any longer(this may also happen on a system catalog tablespace.) that will lead to a conflict on changing the tablespace status flag if stores it within system catalog tables.

Illustration of the DMS table-space address map

address map for DMS TS

DB2 directories and files

  • http://publib.boulder.ibm.com/infocenter/db2luw/v8//topic/com.ibm.db2.udb.doc/admin/c0005420.htm

Illustration of DB2 architechure and process

overview for tuning

Reference

  • http://publib.boulder.ibm.com/infocenter/db2luw/v8//topic/com.ibm.db2.udb.doc/admin/c0005418.htm 

Tablespaces are put into backup pending after a load

DB2 sets tablespace as Backup Pending state after loading data into a table in linear logging database(that is, logretain or userexit is on), whatever the load is successful or failed. the reason is that the load process will not write log file. from the begin time of loading to the end time of loading, there will be a blank segment in log file, and the rollforward recovery can Not jump over the blank segment to apply the later log file.

so database needs a backup after loading to make sure db2 have recovery capicibility.

it's able to use [COPY YES|NO]  or [NONRECOVERABLE] to prevent tablespace go into Backup Pending state. COPY YES will do the backup automatically after loading, and COPY NO and NONRECOVERABLE will give up this backup that means db2 will be not able to recover the database once an serious error occured.


继续阅读 "Tablespaces are put into backup pending after a load" 的剩余内容

Come pending when droping Procedures

Problem Description 

There's no any response for creating or droping any procedures in DB2. Seems it's pending there, without any error returned. This time UPDATE statement on tables could be issued successfully.

Check Process

Check OS disk available

$ df -kl 

Check database configure

db2 => get db cfg |more 

Check system catalog tablespace 

db2 => list tablespaces show detail |more
syscatspace 0x0000 

Cause 

It caused by issuing CREATE or DROP statement without COMMIT or ROLLBACK statement in CLP which is in non-Autocommit mode.

Solution 

After you issue a COMMIT or a ROLLBACK in the CLP or close it, the pending is gone.

We must be very careful when we use client in non-Autocommit mode just like CLPs in this case.

To check the Autocommit mode in CLP issues. Refer to:

set COMMIT mode in db2 clp

db2 => list command options

-c 自动落实 OFF

More 

From this point, we could get more. Most of strange things like this(pending there and no error return) are caused by locking.

In this case, it was only the opertation on procedures being pended, so track on this thread to suppose the syscat tables related with procedures are locked then find the what probably causes it.
 

db2 can not create index on local view

There's an object called index view since MS SQL Server 2000, it's an index which is created on an view which is based on a local table. it is attent to imporve the select performence on the view when this view is based on multi-table and has complex logic.

I try to find a simular thing in DB2, but there's no the simular solution in DB2 v8.2 for now. Instead, I found another thing instested.

DB2 allows creating index on the tables or views in remote data source, such as a database on another host or an XML data source. To be exactly, that's Not true Index, it's Index Specification. It requests that the tables in remote data source have created index in its own system. And it only repeat the index description in local system.

										Local DB2 Env                                            Remote DB2 Env
										

Index Specification    ->    Nickname   - - ->   True Index    ->    Table

See following example in DB2 info center.

  • CREATE INDEX statement
    http://publib.boulder.ibm.com/infocenter/db2luw/v8//topic/com.ibm.db2.udb.doc/admin/r0000919.htm?resultof=%22%63%72%65%61%74%65%22%20%22%63%72%65%61%74%22%20%22%69%6e%64%65%78%22%20%22%73%74%61%74%65%6d%65%6e%74%22%20

Example 3:  The nickname EMPLOYEE references a data source table called CURRENT_EMP. After this nickname was created, an index was defined on CURRENT_EMP. The columns chosen for the index key were WORKDEBT and JOB. Create an index specificationindex. Through this specification, the optimizer will know that the index exists and what its key is. With this information, the optimizer can improve its strategy to access the table. that describes this

   CREATE UNIQUE INDEX JOB_BY_DEPT
ON EMPLOYEE (WORKDEPT, JOB)
SPECIFICATION ONLY

Note: the Nickname is only allowed to be created on tables in local database and on much kind of objects at remote data source. It's not allowed to be created on views in local database.

set COMMIT mode in db2 clp

As default, DB2 CLP will do commit after you issue each DB2 statements or SQL automatically.

If you want to change it instead of issuing COMMIT or ROLLBACK manually, do following.

SQLLIB\BIN> db2
db2 => list command options
    -c   ON
db2 => update command options using c off
db2 => list command options
    -c   OFF

This change will only exists during this session. The setting will lose when you close this CLP and open CLP next time.

following cmd will get the same result with above.

SQLLIB\BIN> db2 list command options
    -c    ON
SQLLIB\BIN> db2 +c
db2 =>
db2 => list command options
    -c    OFF
db2 => quit
SQLLIB\BIN> db2 list command options
    -c    ON

There's also the way to keep the settings forever, do following.

SQLLIB\BIN\> db2 list command options
    -c   ON
SQLLIB\BIN\> db2set db2options=+c
SQLLIB\BIN\> db2 list command options
    -c   OFF

This change will take effection immediately even for others having been opened CLP windows. And will keep along.

Use following cmd set it back to ON. 

SQLLIB\BIN> db2set db2opptions=-c

Reference

表与索引的重命名 RENAME

在DB2 中重命名表或者索引

db2=> RENAME TABLE EMP TO EMPLOYEE
db2=> RENAME TABLE ABC.EMP TO EMPLOYEE
db2=> RENAME INDEX NEW-IND TO IND
db2=> RENAME INDEX ABC.NEW-IND TO IND
posted @ 2007-03-15 15:00 MyJavaWorld 阅读(502) | 评论 (0)编辑 收藏
三个UNIX文件时间ctime、mtime、atime
       我曾经根据文件的状态在指定时间内是否改变写过一个WatchDog来对服务进行监控,其间曾被这三个时间搞混淆,所以觉得很有必要和大家分享我对这三个术语的理解。
      ctime(change time)改变时间:是指文件状态最后一次被改变的时间;
      mtime(modification time)修改时间:是指文件内容最后一次被改变的时间;
      atime(access time)访问时间:是指文件最后一次被读取的时间。
      前两者的区别就在于文件状态的改变既包括文件索引节点的改变,也包括文件内容的改变。也就是说如果你改变了文件内容,则同时更新了ctime和mtime,但是如果你只改变了文件索引节点则只是改变了ctime。atime只有在文件被读取的时侯才会改变。它的改变与文件状态以及文件内容的改变没有直接的联系。
     例如:echo “Hello World” >> myfile 则同时改变了ctime和mtime,atime不变;
     chmod u+x myfile 则只改变了ctime,mtime和atime不变。
     cat myfile,则只改变了atime,ctime和mtime不变
     ps:以上操作均在redhat linux下验证通过
posted @ 2007-03-13 17:51 MyJavaWorld 阅读(1158) | 评论 (0)编辑 收藏
 
 
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DB2/SQL命令大全
2006-12-25 13:21

连接数据库:

  connect to [数据库名] user [操作用户名] using [密码] 

创建缓冲池(8K):

  create bufferpool ibmdefault8k IMMEDIATE  SIZE 5000 PAGESIZE 8 K ;
创建缓冲池(16K)(OA_DIVERTASKRECORD):
  create bufferpool ibmdefault16k IMMEDIATE  SIZE 5000 PAGESIZE 16 K ;
创建缓冲池(32K)(OA_TASK):
  create bufferpool ibmdefault32k IMMEDIATE  SIZE 5000 PAGESIZE 32 K ;

创建表空间:

  CREATE TABLESPACE exoatbs IN DATABASE PARTITION GROUP IBMDEFAULTGROUP PAGESIZE 8K MANAGED BY SYSTEM USING ('/home/exoa2/exoacontainer') EXTENTSIZE 32 PREFETCHSIZE 16  BUFFERPOOL IBMDEFAULT8K  OVERHEAD 24.10 TRANSFERRATE 0.90  DROPPED TABLE RECOVERY OFF;

  CREATE TABLESPACE exoatbs16k  IN DATABASE PARTITION GROUP IBMDEFAULTGROUP PAGESIZE 16K MANAGED BY SYSTEM USING ('/home/exoa2/exoacontainer16k'   ) EXTENTSIZE 32  PREFETCHSIZE 16  BUFFERPOOL IBMDEFAULT16K  OVERHEAD 24.1 TRANSFERRATE 0.90  DROPPED TABLE RECOVERY OFF;

  CREATE TABLESPACE exoatbs32k  IN DATABASE PARTITION GROUP IBMDEFAULTGROUP PAGESIZE 32K MANAGED BY SYSTEM USING ('/home/exoa2/exoacontainer32k'   ) EXTENTSIZE 32  PREFETCHSIZE 16  BUFFERPOOL IBMDEFAULT32K  OVERHEAD 24.1 TRANSFERRATE 0.90  DROPPED TABLE RECOVERY OFF;

GRANT USE OF TABLESPACE exoatbs TO PUBLIC;
GRANT USE OF TABLESPACE exoatbs16k TO PUBLIC;
GRANT USE OF TABLESPACE exoatbs32k TO PUBLIC;

创建系统表空间:

  CREATE TEMPORARY TABLESPACE exoasystmp IN DATABASE PARTITION GROUP IBMTEMPGROUP PAGESIZE 8K  MANAGED BY SYSTEM USING ('/home/exoa2/exoasystmp'   ) EXTENTSIZE 32 PREFETCHSIZE 16 BUFFERPOOL IBMDEFAULT8K  OVERHEAD 24.10 TRANSFERRATE 0.90  DROPPED TABLE RECOVERY OFF;

  CREATE TEMPORARY TABLESPACE exoasystmp16k IN DATABASE PARTITION GROUP IBMTEMPGROUP PAGESIZE 16K MANAGED BY SYSTEM USING ('/home/exoa2/exoasystmp16k'  ) EXTENTSIZE 32 PREFETCHSIZE 16 BUFFERPOOL IBMDEFAULT16K OVERHEAD 24.10 TRANSFERRATE 0.90  DROPPED TABLE RECOVERY OFF;

  CREATE TEMPORARY TABLESPACE exoasystmp32k IN DATABASE PARTITION GROUP IBMTEMPGROUP PAGESIZE 32K MANAGED BY SYSTEM USING ('/home/exoa2/exoasystmp32k') EXTENTSIZE 32 PREFETCHSIZE 16 BUFFERPOOL IBMDEFAULT32K OVERHEAD 24.10 TRANSFERRATE 0.90  DROPPED TABLE RECOVERY OFF;

1. 启动实例(db2inst1):

db2start

2. 停止实例(db2inst1):

db2stop

3. 列出所有实例(db2inst1)

db2ilist

5.列出当前实例:

db2 get instance

4. 察看示例配置文件:

db2 get dbm cfg|more

5. 更新数据库管理器参数信息:

db2 update dbm cfg using para_name para_value

6. 创建数据库:

db2 create db test

7. 察看数据库配置参数信息

db2 get db cfg for test|more

8. 更新数据库参数配置信息

db2 update db cfg for test using para_name para_value

10.删除数据库:

db2 drop db test

11.连接数据库

db2 connect to test

12.列出所有表空间的详细信息。

db2 list tablespaces show detail

13.查询数据:

db2 select * from tb1

14.删除数据:

db2 delete from tb1 where id=1

15.创建索引:

db2 create index idx1 on tb1(id);

16.创建视图:

db2 create view view1 as select id from tb1

17.查询视图:

db2 select * from view1

18.节点编目

db2 catalog tcp node node_name remote server_ip server server_port

19.察看端口号

db2 get dbm cfg|grep SVCENAME

20.测试节点的附接

db2 attach to node_name

21.察看本地节点

db2 list node direcotry

22.节点反编目

db2 uncatalog node node_name

23.数据库编目

db2 catalog db db_name as db_alias at node node_name

24.察看数据库的编目

db2 list db directory

25.连接数据库

db2 connect to db_alias user user_name using user_password

26.数据库反编目

db2 uncatalog db db_alias

27.导出数据

db2 export to myfile of ixf messages msg select * from tb1

28.导入数据

db2 import from myfile of ixf messages msg replace into tb1

29.导出数据库的所有表数据

db2move test export

30.生成数据库的定义

db2look -d db_alias -a -e -m -l -x -f -o db2look.sql

31.创建数据库

db2 create db test1

32.生成定义

db2 -tvf db2look.sql

33.导入数据库所有的数据

db2move db_alias import

34.重组检查

db2 reorgchk

35.重组表tb1

db2 reorg table tb1

36.更新统计信息

db2 runstats on table tb1

37.备份数据库test

db2 backup db test

38.恢复数据库test

db2 restore db test

399\.列出容器的信息

db2 list tablespace containers for tbs_id show detail

40.创建表:

db2 ceate table tb1(id integer not null,name char(10))

41.列出所有表

db2 list tables

42.插入数据:

db2 insert into tb1 values(1,’sam’);

db2 insert into tb2 values(2,’smitty’);

. 建立数据库DB2_GCB 

CREATE DATABASE DB2_GCB ON G: ALIAS DB2_GCB 

USING CODESET GBK TERRITORY CN COLLATE USING SYSTEM DFT_EXTENT_SZ 32 

2. 连接数据库 

connect to sample1 user db2admin using 8301206 

3. 建立别名 

create alias db2admin.tables for sysstat.tables; 

CREATE ALIAS DB2ADMIN.VIEWS FOR SYSCAT.VIEWS 

create alias db2admin.columns for syscat.columns; 

create alias guest.columns for syscat.columns; 

4. 建立表 

create table zjt_tables as 

(select * from tables) definition only; 

create table zjt_views as 

(select * from views) definition only; 

5. 插入记录 

insert into zjt_tables select * from tables; 

insert into zjt_views select * from views; 

6. 建立视图 

create view V_zjt_tables as select tabschema,tabname from zjt_tables; 

7. 建立触发器 

CREATE TRIGGER zjt_tables_del 

AFTER DELETE ON zjt_tables 

REFERENCING OLD AS O 

FOR EACH ROW MODE DB2SQL 

Insert into zjt_tables1 values(substr(o.tabschema,1,8),substr(o.tabname,1,10)) 

8. 建立唯一性索引 

CREATE UNIQUE INDEX I_ztables_tabname 

[size=3]ON zjt_tables(tabname); 

9. 查看表 

select tabname from tables 

where tabname='ZJT_TABLES'; 

10. 查看列 

select SUBSTR(COLNAME,1,20) as 列名,TYPENAME as 类型,LENGTH as 长度 

from columns 

where tabname='ZJT_TABLES'; 

11. 查看表结构 

db2 describe table user1.department 

db2 describe select * from user.tables 

12. 查看表的索引 

db2 describe indexes for table user1.department 

13. 查看视图 

select viewname from views 

where viewname='V_ZJT_TABLES'; 

14. 查看索引 

select indname from indexes 

where indname='I_ZTABLES_TABNAME'; 

15. 查看存贮过程 

SELECT SUBSTR(PROCSCHEMA,1,15),SUBSTR(PROCNAME,1,15) 

FROM SYSCAT.PROCEDURES; 

16. 类型转换(cast) 

ip datatype:varchar 

select cast(ip as integer)+50 from log_comm_failed 

17. 重新连接 

connect reset 

18. 中断数据库连接 

disconnect db2_gcb 

19. view application 

LIST APPLICATION; 

20. kill application 

FORCE APPLICATION(0); 

db2 force applications all (强迫所有应用程序从数据库断开) 

21. lock table

lock table test in exclusive mode 

22. 共享 

lock table test in share mode 

23. 显示当前用户所有表 

list tables 

24. 列出所有的系统表 

list tables for system 

25. 显示当前活动数据库 

list active databases 

26. 查看命令选项 

list command options 

27. 系统数据库目录 

LIST DATABASE DIRECTORY 

28. 表空间 

list tablespaces 

29. 表空间容器 

LIST TABLESPACE CONTAINERS FOR 

Example: LIST TABLESPACE CONTAINERS FOR 1 

30. 显示用户数据库的存取权限 

GET AUTHORIZATIONS 

31. 启动实例 

DB2START 

32. 停止实例 

db2stop 

33. 表或视图特权 

grant select,delete,insert,update on tables to user 

grant all on tables to user WITH GRANT OPTION 

34. 程序包特权 

GRANT EXECUTE 

ON PACKAGE PACKAGE-name 

TO PUBLIC 

35. 模式特权 

GRANT CREATEIN ON SCHEMA SCHEMA-name TO USER 

36. 数据库特权 

grant connect,createtab,dbadm on database to user 

37. 索引特权 

grant control on index index-name to user 

38. 信息帮助 (? XXXnnnnn ) 

例:? SQL30081 

39. SQL 帮助(说明 SQL 语句的语法) 

help statement 

例如,help SELECT 

40. SQLSTATE 帮助(说明 SQL 的状态和类别代码) 

? sqlstate 或 ? class-code 

41. 更改与"管理服务器"相关的口令 

db2admin setid username password 

42. 创建 SAMPLE 数据库 

db2sampl 

db2sampl F:(指定安装盘) 

43. 使用操作系统命令 

! dir 

44. 转换数据类型 (cast) 

SELECT EMPNO, CAST(RESUME AS VARCHAR(370)) 

FROM EMP_RESUME 

WHERE RESUME_FORMAT = 'ascii' 

45. UDF

要运行 DB2 Java 存储过程或 UDF,还需要更新服务器上的 DB2 数据库管理程序配置,以包括在该机器上安装 JDK 的路径 

db2 update dbm cfg using JDK11_PATH d:sqllibjavajdk 

TERMINATE 

update dbm cfg using SPM_NAME sample 

46. 检查 DB2 数据库管理程序配置 

db2 get dbm cfg 

47. 检索具有特权的所有授权名 

SELECT DISTINCT GRANTEE, GRANTEETYPE, 'DATABASE' FROM SYSCAT.DBAUTH 

UNION 

SELECT DISTINCT GRANTEE, GRANTEETYPE, 'TABLE ' FROM SYSCAT.TABAUTH 

UNION 

SELECT DISTINCT GRANTEE, GRANTEETYPE, 'PACKAGE ' FROM SYSCAT.PACKAGEAUTH 

UNION 

SELECT DISTINCT GRANTEE, GRANTEETYPE, 'INDEX ' FROM SYSCAT.INDEXAUTH 

UNION 

SELECT DISTINCT GRANTEE, GRANTEETYPE, 'COLUMN ' FROM SYSCAT.COLAUTH 

UNION 

SELECT DISTINCT GRANTEE, GRANTEETYPE, 'SCHEMA ' FROM SYSCAT.SCHEMAAUTH 

UNION 

SELECT DISTINCT GRANTEE, GRANTEETYPE, 'SERVER ' FROM SYSCAT.PASSTHRUAUTH 

ORDER BY GRANTEE, GRANTEETYPE, 3 

create table yhdab 

(id varchar(10), 

password varchar(10), 

ywlx varchar(10), 

kh varchar(10)); 

create table ywlbb 

(ywlbbh varchar(8), 

ywmc varchar(60)) 

48. 修改表结构 

alter table yhdab ALTER kh SET DATA TYPE varchar(13); 

alter table yhdab ALTER ID SET DATA TYPE varchar(13); 

alter table lst_bsi alter bsi_money set data type int; 

insert into yhdab values 

('20000300001','123456','user01','20000300001'), 

('20000300002','123456','user02','20000300002'); 

49. 业务类型说明 

insert into ywlbb values 

('user01','业务申请'), 

('user02','业务撤消'), 

('user03','费用查询'), 

('user04','费用自缴'), 

('user05','费用预存'), 

('user06','密码修改'), 

('user07','发票打印'), 

('gl01','改用户基本信息'), 

('gl02','更改支付信息'), 

('gl03','日统计功能'), 

('gl04','冲帐功能'), 

('gl05','对帐功能'), 

('gl06','计费功能'), 

('gl07','综合统计') 

备份数据库:
CONNECT TO EXOA;
QUIESCE DATABASE IMMEDIATE FORCE CONNECTIONS;
CONNECT RESET;
BACKUP DATABASE EXOA TO "/home/exoa2/db2bak/" WITH 2 BUFFERS BUFFER 1024 PARALLELISM 1 WITHOUT PROMPTING;
CONNECT TO EXOA;
UNQUIESCE DATABASE;
CONNECT RESET;

以下是小弟在使用db2move中的一些经验,希望对大家有所帮助。 

 db2   connect   to  YOURDB   
连接数据库 

 db2look -d  YOURDB  -a -e -x -o creatab.sql 
导出建库表的SQL 

 db2move   YOURDB  export 
用db2move将数据备份出来 

 vi   creatab.sql 
如要导入的数据库名与原数据库不同,要修改creatab.sql中CONNECT 项 
如相同则不用更改 

 db2move  NEWDB  load 
将数据导入新库中 

在导入中可能因为种种原因发生中断,会使数据库暂挂 
db2    list tablespaces   show   detail 
如: 
      详细说明: 
     装入暂挂 
 总页数                          = 1652 
 可用页数                        = 1652 
 已用页数                         = 1652 
 空闲页数                         = 不适用 
 高水位标记(页)                 = 不适用 
 页大小(字节)                   = 4096 
 盘区大小(页)                   = 32 
 预读取大小(页)                 = 32 
 容器数                           = 1 
 状态更改表空间标识                    = 2 
 状态更改对象标识                      = 59 

 db2 select tabname,tableid from syscat.tables where tableid=59 
查看是哪张表挂起 

表名知道后到db2move.lst(在db2move  YOURDB  export的目录中)中找到相应的.ixf文件 
 db2 load from tab11.ixf of ixf terminate into db2admin.xxxxxxxxx 
tab11.ixf对应的是xxxxxxxxx表 

数据库会恢复正常,可再用db2 list tablespaces show detail查看

30.不能通过GRANT授权的权限有哪种?

SYSAM

SYSCTRL

SYSMAINT

要更该述权限必须修改数据库管理器配置参数

31.表的类型有哪些?

永久表(基表)

临时表(说明表)

临时表(派生表)

32.如何知道一个用户有多少表?

SELECT*FROMSYSIBM.SYSTABLESWHERECREATOR='USER'

33.如何知道用户下的函数?

select*fromIWH.USERFUNCTION

select*fromsysibm.SYSFUNCTIONS

34.如何知道用户下的VIEW数?

select*fromsysibm.sysviewsWHERECREATOR='USER'

35.如何知道当前DB2的版本?

select*fromsysibm.sysvERSIONS

36.如何知道用户下的TRIGGER数?

select*fromsysibm.SYSTRIGGERSWHERESCHEMA='USER'

37.如何知道TABLESPACE的状况?

select*fromsysibm.SYSTABLESPACES

38.如何知道SEQUENCE的状况?

select*fromsysibm.SYSSEQUENCES

39.如何知道SCHEMA的状况?

select*fromsysibm.SYSSCHEMATA

40.如何知道INDEX的状况?

select*fromsysibm.SYSINDEXES

41.如何知道表的字段的状况?

select*fromsysibm.SYSCOLUMNSWHERETBNAME='AAAA'

42.如何知道DB2的数据类型?

select*fromsysibm.SYSDATATYPES

43.如何知道BUFFERPOOLS状况?

select*fromsysibm.SYSBUFFERPOOLS

44.DB2表的字段的修改限制?

只能修改VARCHAR2类型的并且只能增加不能减少.

45.如何查看表的结构?

DESCRIBLETABLETABLE_NAME

OR

DESCRIBLESELECT*FROMSCHEMA.TABLE_NAME

 
 

     
 
posted @ 2006-12-28 16:57 MyJavaWorld 阅读(2735) | 评论 (0)编辑 收藏

DB2 UDB中用户出口程序是如何工作的?

 

采用用户出口程序与DB2 UDB共同工作背后的基本思想是提供一种归档和检索数据库日志文件的方法以实现日志冗余处理并从易失性介质上转储出来。重要的,值得注意的是,根据你的特殊需求,在用户出口程序当中,除了能实现归档和检索日志之外,你还可以实现其他的操作。

 

如果一个数据库需要采用归档日志文件来进行恢复,在DB2 UDB中实行用户出口程序策略将不能恢复100%的事务。用户出口程序只是一种通过拷贝已经存在的日志文件到一个安全的地方来为其提供更多保护的方法。它是数据完整性策略中的一部分,而且是重要的一部分。

 

编译了用户出口程序之后,可执行程序db2uext2被放置在数据库管理器可以找到的目录当中。在UNIX©中,这个目录是/sqllib/adm;在Windows©中,是Program FilesIBMSQLLIBBIN。

 

除非数据库管理器知道用户出口程序是可用的,不然它不会调用db2uext2。让数据库管理器知道db2uext2可以被调用的唯一方法是将数据库配置参数userexit设置为on。一旦这个参数被设定好而且DB2实例被重复利用了,数据库管理器将每五分钟调用一次用户出口程序来检查那些可以被归档到程序相关的归档目录的日志文件。

 

如果数据库的恢复是必要的,在前滚操作期间,数据库管理器将调用db2uext2把归档日志文件拷贝回活动的日志目录当中。然后,日志文件被再次运用到重建的数据库中。

 

让我们看看被数据库管理器生成的到用户出口程序的调用的格式。注意,这一信息也可以在用户出口示例程序的注释部分找到。

db2uext2 -OS -RL

-RQ -DB -NN

-LP -LN [-AP]

 

其中:

os=操作系统

release=DB2发行版本

request= 'ARCHIVE' 或 'RETRIEVE'

dbname=数据库名

nodenumber=节点号

logpath=日志文件目录

logname=日志文件名

logsize=日志文件大小(可选)

startingpage=以4k页为单位的起始偏移量(可选)

adsmpasswd=ADSM密码(可选)

 

注意:只有当logpath为裸设备时才使用logsize和startingpage。

 

归档或者从磁盘检索日志文件遵从以下命名规则:

归档:归档路径+数据库名+节点号+日志文件名

检索:检索路径+数据库名+节点号+日志文件名

 

比如:如果归档的路径为”c:mylogs”,

检索路径是“c:mylogs”,

数据库名是“SAMPLE”,

节点号是 NODE0000,

文件名是 S0000001.LOG,

日志文件将是:

归档到 - c:mylogsSAMPLENODE0000S0000001.LOG

检索自 - c:mylogsSAMPLENODE0000S0000001.LOG

以下描述了用户出口程序中的逻辑是如何运转的:

1)  安装信号处理程序。

2)  验证传递的参数个数。

3)  验证操作请求。

4)  开始审计跟踪(如果有此请求)。

5)  根据操作需求的不同获取以下路径中的一个:

a)  如果操作需求为归档一个文件,将日志文件从日志路径拷贝到归档路径中。

i) 如果没有找到日志文件,执行第6点。

 

b)  如果操作需求是检索一个文件,将日志文件从检索路径拷贝到日志路径中。

i) 如果没有找到日志文件,执行第6点。

6) 将错误记入日志(如果要求或者有需要的话)。

7)  结束审计跟踪(如果有请求)。

8)  以适当的返回码退出。

 

手工调用用户出口程序来归档日志文件是可以的,但最好还是使用ARCHIVE LOG命令以便在定义以上参数时不会因为你的原因导致错误。在这篇文章的末尾,可以找到关于ARCHIVE LOG命令的链接。

 

日志文件术语

 

DB2 中用户出口程序的基本功能是将日志文件拷贝到活动日志目录或反之。这里,值得指出一些术语来阐明活动的日志目录被置于何处以及数据库日志文件的状态如何。

 

活动日志目录:

 

该目录被置于你的数据库目录中。在Windows中,如果在C:中创建了一个叫做SAMPLE的单一数据库且实例名为db2inst1,则将会出现以下的目录结构:

 

C:DB2INST1NODE0000SQL000001SQLOGDIR

 

SQL00001是SAMPLE数据库的数据库目录,SQLOGDIR 是活动日志目录。

 

以下的图1显示了Windows操作系统上的活动日志目录:

PATH o:extrusionok="f" gradientshapeok="t" o:connecttype="rect" />SHAPE id=_x0000_i1025 style="WIDTH: 299.25pt; HEIGHT: 180.75pt" type="#_x0000_t75" />/P>

 

图 1活动日志目录

日志文件状态

 

在活动日志目录中,日志文件可以是活动日志,也可以是联机归档日志。活动日志是那些被 DB2 用于当前事务处理和崩溃恢复的日志。联机归档日志是那些 DB2 UDB 进行常规处理时不再需要,而进行数据库恢复时可能还会需要的日志。当实现用户出口程序时,这些联机归档日志将最终以归档日志目录中的副本形式出现。

 

既然 DB2 UDB 中用户出口程序的目的是将数据库日志拷贝到归档目录中,你将最终在活动日志目录(缺省为 SQLOGDIR)中得到重复的日志文件。你可能考虑删除这些重复的联机归档日志以释放文件系统空间。在从数据库目录中除去这些日志之前,要十分小心地确认它们是否已经将成功地被复制到归档目录中。还必须确保数据库管理器进行崩溃恢复时不再需要它们。要确定你的活动日志目录中哪些日志文件不为正常处理所需要,可用通过以下命令检查数据库配置:

        

     db2 "get db cfg for sample"

 

这条命令的数据库配置输出结果将包含第一个活动日志文件,如:

First active log file = S000009.LOG

 

在如上所示的输出当中,日志文件S000009.LOG是数据库当前的活动日志。任何编号比该日志文件小的日志文件都被看作联机归档日志。

 

这里有一个例子:

 

在这个场景中,活动日志目录中有日志文件 S000000.LOG - S000009.LOG,归档日志目录中有 S000000.LOG - S000008.LOG。因为 S000009.LOG 是第一个活动日志文件,所以,可以从活动日志目录中移走 S000001.LOG - S000008.LOG 以释放磁盘空间。S000009.LOG 文件必须保留在活动日志目录中,因为它仍然被当前事务使用。

 

同样可以通过检查数据库历史文件来查看活动日志目录中哪些日志文件不再有用。以下命令将列出数据库备份信息:

 

     db2 "list history backup all for database sample"

 

以下是该命令的输出结果的一个例子:

 

List History File for sample

Number of matching file entries = 4

Op Obj Timestamp+Sequence Type Dev Earliest Log Current  Log

-- --- ------------------ ---- --- ------------------------

B D 20030416162026001 F D S0000010.LOGS0000014.LOG

------------------------------------------------------------

Contains 2 tablespace(s):

00001 SYSCATSPACE

00002 USERSPACE1

------------------------------------------------------------

 

在上面的输出中,最早的日志将表示,需要 S0000010.LOG 及其之后的任何日志。 S00000010.LOG 之前的任何日志可以被安全的删除。再次提醒,在从活动日志目录中删除日志文件之前,验证在活动日志目录中存在这些日志文件的拷贝是十分重要的。

 

虽然可以手动的从活动日志目录中删除日志文件,删除联机归档日志文件的安全方法是通过prune logfile命令。该命令可以用来删除活动归档目录中的日志文件。在下面的示例中,以下命令将删除日志文件 S000000.LOG - S000008.LOG:

     db2 "prune logfile prior to S000009.LOG"

 

注意:根据您的恢复策略,可能会出现之前的前滚操作在数据库上执行的场景。归档目录中的老日志文件可能被同名的新日志文件所覆盖,从而阻止你使用旧日志文件对数据库进行时间点恢复。对用户出口程序的设计程序员来说,考虑类似这样的情况是很重要的。

 

设置用户出口

 

在本文中,我们将采用DB2提供的db2uext2.cdisk样例c程序,它位于你的c目录当中。在UNIX中,c目录位于/sqllib/samples。Windows中,这目录位于Program Files/IBM//samples。

 

在Windows中设置用户出口

 

修改和编译用户出口程序

1.  创建名为C:mylogs的目录

2.  将C:Program filesIBMSQLLIBsamplescdb2uext2.cdisk拷贝到一个工作目录当中

3.  对于本示例,用户出口程序的以下部分应该得以验证以反映路径 c:\mylogs\

 

#define ARCHIVE_PATH "c:\mylogs\"

#define RETRIEVE_PATH "c:\mylogs\"

#define AUDIT_ACTIVE 1 /* enable audit trail logging */

#define ERROR_ACTIVE 1 /* enable error trail logging */

#define AUDIT_ERROR_PATH "c:\mylogs\"

                 /* path must end with a slash */

#define AUDIT_ERROR_ATTR "a" /* append to text file */

#define BUFFER_SIZE 32

    /* # of 4K pages for output buffer */

 

4.  确定在你的系统中安装了被支持的C编译器(比如,Microsoft Visual Studio)而且环境中有该编译器的路径。

5.  通过命令行,将db2uext2.cdisk更名为db2uext2.c并构建:

cl db2uext2.c

一旦程序被编译,将创建db2uext2.exe和db2uext2.obj文件。

6.  将可执行文件db2uext2.exe放到/SQLLIB/BIN目录当中从而使数据库管理器能够定位并执行它用以归档和检索日志。

 

为用户出口创建并准备数据库

7.  在 DB2 命令窗口中用 db2sampl 命令创建 SAMPLE 数据库。这将使你对下面的示例使用样本表。

db2sampl

8.  更新数据库配置文件以便为数据库打开用户出口。请注意:只能为一个数据库分配用户出口程序,因为 bin 目录被所有 DB2 实例共享。

db2 "update db cfg for sample using userexit on"

db2stop force

<span lang="EN-US" style="FONT-SIZE: 10pt; COLOR: black; FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 宋体; mso-

/P>
posted @ 2006-12-08 18:12 MyJavaWorld 阅读(406) | 评论 (0)编辑 收藏