Harvard University Oracle Database Administration Session 9 Managing the Environment

Harvard University DBA Goals  A proactive DBA reduces the number of weekends and off-hours worked  Setup some routines  Review the database to see what is ‘normal’  What are the growth patterns  Number of users logged in  The CPU and memory usage

Harvard University DBA Goals  The disks ‘hit’ the most  Check the alert.log for ora errors  Check for trace files  When you do these things regularly, you will notice the abnormal more easily

Harvard University Health Checks  Database  Application  System

Harvard University Release Management  Development  Test/Integration  Production  Patch  Interfaces  Conversion  Security

Harvard University Release Management  Systems  O/S  Backend  Middle Tier  Number of Users  Batch schedule  Performance Test

Harvard University Management Framework  Monitoring Framework  Automation  Batch Control  Scheduling  Production Control

Harvard University Environment Management  Wholistic Approach – Database – Middle Tier – Data Loading – Linked databases – Backups

Harvard University Environment Management  Application User perspective – Total number of Users – Max concurrent Users – Length of data loads – Uptime requirement – Must be available at……  Manage to their requirements

Harvard University DBA Tasks  Is it running……  “ps –eaf | grep dbw” tests to see if the database is up and running  “ps –eaf | grep lsnrctl” tests if the listener is running  sqlplus or some user Password ******* Tests if you can connect to the database

Harvard University Alert Log  Alert.log – Located in /$ORACLE_BASE/admin/ /diag/bdump – It shows when the database was started – When a log switch occurred – Shows the non-default parameters from the init.ora

Harvard University Alert Log – Any ddl commands to change the structure of the database – Space allocation errors – When trace files were created and where they are located – When the database was shutdown or started

Harvard University Alert Log  This file is not adjusted by Oracle, it is always appended to, until you change it.  You can rename it, edit it, or reduce it’s size  When it is renamed, Oracle will create a new file automatically

Harvard University Trace Files  When there are internal errors in a user session or with a background process, Oracle creates a trace file  They are to help in debugging a problem  Trace files, created by a background process, will have the name of the background process as part of the file name

Harvard University Trace Files  The trace file of a user process will have the process ID, in the file name  The following init.ora parameters relate to trace files – max_dump_file_sizeunlimited size – background_dump_destbackground processes – user_dump_destuser sessions traces

Harvard University Type of Views  Dba_  User_  All_  V$….  X$..

Harvard University Views  dba_segments  dba_rollback_segs  dba_objects  v$rollstat  v$rollname

Harvard University Views  dba_extents  dba_tables  dba_indexes  v$sqltext

Harvard University Instance Level  v$instance  v$database  v$sga  v$sgastat  v$parameter  v$option  v$version  v$license

Harvard University Session Level  v$session  v$transaction  v$process  v$access

Harvard University Database Structure  v$tablespace  v$datafile  v$dbfile  v$dblink  v$datafile_header

Harvard University Performance  v$waitstat  v$filestat  v$sysstat

Harvard University All V$ Views  select name from v$fixed_table where name like ‘v%' order by name

Harvard University CREATE OR REPLACE VIEW DBA_SEGMENTS ( OWNER, SEGMENT_NAME, PARTITION_NAME, SEGMENT_TYPE, TABLESPACE_NAME, HEADER_FILE, HEADER_BLOCK, BYTES, BLOCKS, EXTENTS, INITIAL_EXTENT, NEXT_EXTENT, MIN_EXTENTS, MAX_EXTENTS, PCT_INCREASE, FREELISTS, FREELIST_GROUPS, RELATIVE_FNO, BUFFER_POOL ) AS select owner, segment_name, partition_name, segment_type, tablespace_name, header_file, header_block, bytes, blocks, extents, initial_extent, next_extent, min_extents, max_extents, pct_increase, freelists,freelist_groups, relative_fno, buffer_pool from sys_dba_segs Example of a View

Harvard University dba_segments Name Null? Type OWNER VARCHAR2(30) SEGMENT_NAME VARCHAR2(81) PARTITION_NAME VARCHAR2(30) SEGMENT_TYPE VARCHAR2(18) TABLESPACE_NAME VARCHAR2(30) HEADER_FILE NUMBER HEADER_BLOCK NUMBER BYTES NUMBER BLOCKS NUMBER EXTENTS NUMBER INITIAL_EXTENT NUMBER NEXT_EXTENT NUMBER MIN_EXTENTS NUMBER MAX_EXTENTS NUMBER PCT_INCREASE NUMBER FREELISTS NUMBER FREELIST_GROUPS NUMBER RELATIVE_FNO NUMBER BUFFER_POOL VARCHAR2(7)

Harvard University Examples  select substr(segment_name,1,19) segment_name, extents from dba_segments where tablespace_name = ‘TS‘  select substr(table_name,1,19) table_name, freelists from dba_tables where tablespace_name = ‘TS'

Harvard University DBA Views set pagesize 9999 col owner format a10 col object_name format a40 select owner,object_name,object_type from dba_objects where (object_name like 'DBA_%' or object_name like 'V$%' ) and owner in ('SYS', 'SYSTEM', 'PUBLIC') order by owner,object_name

Harvard University Space Management  A database stores data  We must have enough free space available, to ensure that will continue to occur  Tablespace available  Segment space available inside the tablespace  Can we extend each segment

Harvard University Storage Information  select segment_name, segment_type,extents from dba_segments where tablespace_name = ‘DATA‘ and segment_type = ‘TABLE'  This will tell you what number of extents each table has, in a specific tablespace

Harvard University Storage Information  Change table to index and get the values for indexes

Harvard University Use this command to alter an existing tablespace in one of the following ways: * to add datafile(s) * to rename datafiles * to change default storage parameters * to take the tablespace online or offline * to begin or end a backup * to allow or disallow writing to a tablespace * to change the default logging attribute of the tablespace * to change the minimum tablespace extent length ALTER TABLESPACE

Harvard University ALTER TABLESPACE tablespace {ADD DATAFILE 'filespec‘ [AUTOEXTEND {OFF | ON [NEXT integer [K | M] ] [MAXSIZE { UNLIMITED | integer [K | M] } ] } ] [, 'filespec' [AUTOEXTEND {OFF | ON [NEXT integer [K | M] ] [MAXSIZE {UNLIMITED | integer [K | M] } ] } ] ]... Tablespace management

Harvard University | RENAME DATAFILE 'filename' [, 'filename']... TO 'filename' ['filename']... | COALESCE | DEFAULT STORAGE storage_clause | MINIMUM EXTENT integer [K | M] | ONLINE | OFFLINE [NORMAL | TEMPORARY | IMMEDIATE] | {BEGIN | END} BACKUP | READ {ONLY | WRITE} | PERMANENT | TEMPORARY} Tablespace management

Harvard University Tablespace management example  CREATE TABLESPACE TOOLS DATAFILE '/u51/oradata/dev/tools01.dbf' SIZE 50M AUTOEXTEND OFF EXTENT MANAGEMENT LOCAL AUTOALLOCATE LOGGING ONLINE

Harvard University Tablespace management example  ALTER TABLESPACE TOOLS ADD DATAFILE '/u51/oradata/dev/tools02.dbf' SIZE 200M /  ALTER DATABASE DATAFILE '/u51/oradata/dev/tools01.dbf' RESIZE 100M /

Harvard University Tablespace management example  ALTER DATABASE DATAFILE '/u08/oradata/test/datafile01.dbf' RESIZE 200M;  ALTER DATABASE DATAFILE '/u08/oradata/test/datafile01.dbf' AUTOEXTEND ON  ALTER DATABASE DATAFILE '/u08/oradata/test/tools01.dbf' AUTOEXTEND ON NEXT 200M MAXSIZE 1000M

Harvard University Sql creating sql  select ' alter database datafile ''' || file_name || ''' resize ' || to_char ( bytes/1024/ &Size ) || 'M ; ' from dba_data_files where tablespace_name = upper ( '&tablespace_name' ) and rownum < 2

Harvard University Create tablespace set heading off set verify off select distinct ( substr ( name, 1, 4 ) ) from v$datafile / select '&Press any key to continue... ' from dual / Prompt Enter Tablespace_name : Accept Tablespace_name select ' create tablespace &&tablespace_name datafile ''/u&filename/oradata/'|| value || '/&&tablespace_name' || '01.dbf'' size &Size M; ' from dual, v$parameter where name = 'instance_name' /

Harvard University Object Status Examples  select count(*) from dba_objects where status = 'INVALID‘  select object_name, object_type from dba_objects where status = 'INVALID'

Harvard University Object Modifications  select owner,object_name, object_type, status, timestamp from dba_objects where substr(timestamp,1,10) = to_char(sysdate-1, 'YYYY-MM-DD') order by owner,object_name  This will tell what objects changed since the day before

Harvard University User Sessions  desc v$session  SQL> select status, count(*) from v$session group by status; STATUS COUNT(*) ACTIVE 18 INACTIVE 16

Harvard University User Sessions  A value of inactive means that no SQL statement is running at the moment  The total number of users connected is the addition of both count values  What is each user doing, etc

Harvard University Users  CREATE USER You can assign the following properties to the user: * default tablespace * temporary tablespace * quotas for allocating space in tablespaces

Harvard University CREATE USER user IDENTIFIED {BY password | EXTERNALLY } [ DEFAULT TABLESPACE tablespace | TEMPORARY TABLESPACE tablespace | QUOTA { integer [K | M] | UNLIMITED } ON tablespace [ QUOTA { integer [K | M] | UNLIMITED } ON tablespace ] Create User

Harvard University ALTER USER user { IDENTIFIED {BY password | EXTERNALLY} | DEFAULT TABLESPACE tablespace | TEMPORARY TABLESPACE tablespace | QUOTA { integer [K | M] | UNLIMITED} ON tablespace [ QUOTA { integer [K | M] | UNLIMITED} ON tablespace]... | DEFAULT ROLE { role [, role]... | ALL [EXCEPT role [, role]...] | NONE} }... Alter User

Harvard University Roles  Connect role  Resource role  DBA role  Object privileges  System Privileges

Harvard University Connect  select * from dba_sys_privs where grantee = ‘connect’  CONNECTCREATE VIEWNO  CONNECTCREATE TABLENO  CONNECTALTER SESSIONNO  CONNECTCREATE CLUSTERNO  CONNECTCREATE SESSIONNO  CONNECTCREATE SYNONYMNO  CONNECTCREATE SEQUENCENO  CONNECTCREATE DATABASE LINKNO

Harvard University RESOURCE Role  select * from dba_sys_privs where grantee = ‘RESOURCE’  RESOURCECREATE TYPENO  RESOURCECREATE TABLENO  RESOURCECREATE CLUSTERNO  RESOURCECREATE TRIGGERNO  RESOURCECREATE OPERATORNO  RESOURCECREATE SEQUENCENO  RESOURCECREATE INDEXTYPENO  RESOURCECREATE PROCEDURENO

Harvard University DBA Role  select * from dba_sys_privs where grantee = ‘DBA’

Harvard University GRANT { object_priv | ALL [PRIVILEGES] } [ ( column [, column]...) ] [, { object_priv | ALL [PRIVILEGES] } [ ( column [, column]...) ] ]... ON [ schema.| DIRECTORY] object TO { user | role | PUBLIC}... [ WITH GRANT OPTION] GRANT (Object Privileges) Roles

Harvard University GRANT { system_priv | role} [, { system_priv | role} ]... TO { user | role | PUBLIC} [, { user | role | PUBLIC} ]... [ WITH ADMIN OPTION] GRANT (System Privileges and Roles) Roles

Harvard University Rebuild Indexes  Rebuild indexes using the following  Alter index index_name rebuild storage (initial 10M, next 10M, pctincrease 0) tablespace indexes  We can move indexes to another tablespace  There must be enough space to hold the old index and the new index, in the tablespace

Harvard University Rebuild Indexes  It can be used to reclaim unusable space  This occurs when there are a large amounts of deletions from a table

Harvard University Shared Memory  ipcs - report inter-process communication facilities status  ipcrm - remove a message queue, semaphore set, or shared memory ID  Oradebug – be very careful using this

Harvard University Suggestions  Create a script that will document your database  Run it regularly. It will give you a quick overview and provide a baseline, if things change

Harvard University Assignment 3  Create a database documentation script. Include the following – Tablespaces – Tablespace free space – Datafiles – Redo logs – Database objects – Segments

Harvard University Assignment 3 – Other areas of interest – Process information – Session information – Extents used by tables/indexes – Free space in tablespace