Tag: Oracle Blog .

Bulid Logical Database

Posted on by Osama Mustafa in Database
I Post Earlier What is the Different Between Logical Database and Standby Database , Both Are Type For Data Guard .

Today i will take about how to configure Logical Database , to do this you must first create Physical Standby Which i mention it before , And you can Follow the link .

These steps for 10g,  Now After create physical Standby Database , And Make sure its working Without any problem , You Have to follow the below steps to Create Oracle Logical Standby.


Steps to convert Standby Database to Logical Standby Database :

Step #1 : 

in this step logminer Dictionary Must be Built into redo data. ( Build LogMiner Tables for Dictionary)

On Primary

SQL> begin
  2  dbms_logstdby.build;
  3  end ;
  4  /

OR

 SQL> execute dbms_logstdby.build;

Step #2:

Now we have stop Managed recovery between primary and standby :

On Standby :

SQL> alter database recover managed standby database cancel ;

Database altered.

Step #3 :

Convert Physical Standby to Logical Standby .

On Standby :

SQL> alter database recover to logical standby stdby ;

Database altered.

Notices : If this command hang and take to much Time then Back to step #1 and did it again .

Step #4:

On Standby ( New Logical)  we open it in Resetlog mode .

On New Logical ( Standby) :

SQL> shutdown immediate ;
ORA-01507: database not mounted

ORACLE instance shut down.

SQL> startup mount ;
ORACLE instance started.

Total System Global Area  839282688 bytes
Fixed Size                  2217992 bytes
Variable Size             532678648 bytes
Database Buffers          301989888 bytes
Redo Buffers                2396160 bytes
Database mounted.

SQL>
SQL>
SQL> alter database open resetlogs ;

Database altered.

Step #5:

Start Apply Service On logical

SQL> alter database start logical standby apply ;

Database altered.

OR

SQL> alter database start logical standby apply immediate ;
Database altered.

Just As Check if everything Goes Fine :

SQL> select database_role , Name from v$database ;

DATABASE_ROLE    NAME
—————- ———
LOGICAL STANDBY  STDBY

Thank you
Osama Mustafa

ora-00845 memory_target not supported on this system

Posted on by Osama Mustafa in Database
The Error Will be Appear like the following : 

SQL> startup nomount;
ORA-00845: MEMORY_TARGET not supported on this system

 Cause :

This error comes up because you tried to use the Automatic Memory Management (AMM) feature of Oracle 11g R2. Well done, but it seems that your shared memory filesystem (shmfs) is not big enough. So let’s look at the steps necessary to enlarge your shared memory filesystem to avoid the error above.

Solution 

mount -t tmpfs shmfs -o size= /dev/shm

Thank you
Osama Mustafa

Logical Standby Vs Physical Standby

Posted on by Osama Mustafa in Database
What is the difference between these two Data Guard configuration , When To Use them :

Physical Standby:

1- Physical Standby Database Its exactly same As Primary Database.
2-  In Physical Data Guard The archivelog Applied directly after transfer from primary database (FTP)

Properties of Physical Standby

1- Maintain Is Easy.
2- Creation is Easy .
3- Copy Of your Primary Database ( Disaster Recovery Solution ).

Usage :

High availability solutions Or disaster recovery Solution.

Logical Standby

1 – Opposite Of standby Database , Which is not Match primary Database .
2 – This Kind Of Configuration can be Opened in Read Only Mode .
3 – can have additional materialized views and indexes added for faster performance
4 – LogMiner Techniques to transfer Archivelog.

Properties Of Logical Database :

1 – Open In Read only Mode .
2 – Sometimes its used as RollBack Solution In Upgrade ,

Usage:

1 – reporting Database to avoid overhead in primary database.
2 – Query Database .

How they Works :

Regarding to Oracle documentation  :

LNS (log-write network-server) and ARCH (archiver) processes running on the primary database select archived redo logs and send them to the standby database, where the RFS (remote file server) background process within the Oracle instance performs the task of receiving archived redo-logs originating from the primary database.

Alternatively, a supplementary mechanism may transfer the archived redo logs. On the standby database a Fetch Archive Log (FAL) client monitors for gaps in the sequence of received logs. If it finds a gap, it may invoke one or more Fetch Archive Log (FAL) servers to run on the primary database to forward the missing item(s).

Once the archived redo logs have arrived, other processes (such as an ARCH (Archiver process), an MRP (Managed Recovery Process), and/or an LSP (Logical Standby Process)) may set about applying the log contents to the standby database.

 Conclusion :

The difference between physical and logical standby is in the way the changes from the primary are applied. Both created as an exact image of the primary database. Both receive redo logs from the primary database.

 Refernce :
 Oracle DataGuard architecture 

Thank you
Osama mustafa

Some Command To Deal With Standby Database

Posted on by Osama Mustafa in Database
Open Standby In Read Only :

    SQL> RECOVER MANAGED STANDBY DATABASE CANCEL;
    SQL> ALTER DATABASE OPEN READ ONLY;

Back to Mount Point ( Same as Before Open in Read Only ) :

    SQL > shutdown;
    SQL > startup nomount
    SQL > alter database mount standby database
    SQL > alter database recover managed standby database disconnect from session;

Switch Over Primary As Standby , And Standby As Primary

Primary Database : Prim
Standby Database : Stdby

On Prim :

SQL> ALTER DATABASE COMMIT TO SWITCHOVER TO STANDBY;
SQL> SHUTDOWN NORMAL;
SQL> STARTUP NOMOUNT;
SQL> ALTER DATABASE MOUNT STANDBY DATABASE;

On standby:

SQL> ALTER DATABASE COMMIT TO SWITCHOVER TO PRIMARY;
SQL> SHUTDOWN;
SQL> STARTUP;


On Prim :

    SQL> ALTER DATABASE RECOVDR MANAGED STANDBY DATABASE;

On standby:

SQL> ALTER SYSTEM ARCHIVE LOG START;
SQL> ALTER SYSTEM SWITCH LOGFILE

Thank you
Osama Mustafa

Step By Step to Create Phyiscal Standby Dastabase 10g

Posted on by Osama Mustafa in Articles, Database
I Post Earlier Some Topics About Dealing with Data Guard , Today i will start Mention Steps How To Create Data Guard Standby Database Manually . Its Long East Steps .Just Follow Them :


primary Information :
Instance Name : prim
Hostname : PrimDB10g

Standby Information :
Instance Name : Stdby
Hostname : StdbyDB10g

Some Note :
1-On Standby Hostname Just install Database Software without Create Any Database.
2-Primary Database and Standby Database should be able to ping .
3-Primary and Standby Should be The Same .


Step #1 : On primary Database 

-Primary Database Should be in Archive log mode.


SQL> archive log list;
Database log mode              No Archive Mode
Automatic archival             Disabled
Archive destination            USE_DB_RECOVERY_FILE_DEST
Oldest online log sequence     0
Current log sequence           1

SQL > Shutdown immediate ;
SQL > Startup mount ;
SQL > Alter database archivelog ;
SQL > Alter database open ;

– Enable Force Logging to make sure  takes precedence and all operations are logged
  into the redo logs.

  SQL> ALTER DATABASE FORCE LOGGING;

-Create Password Since password file should be the same on Both , you can create it on Primary Database and Copy to Standby with Change name .

[oracle@PrimDB10g]$ orapwd file=@ORACLE_HOME/db/orapwprim password=oracle force=y

Step #2 :Adding Standby Logfile .

SQL> ALTER DATABASE ADD STANDBY LOGFILE GROUP 4  ‘/u01/app/oracle/oradata/prim/stby04.log’ size 50m;

SQL> ALTER DATABASE ADD STANDBY LOGFILE GROUP 5   ‘/u01/app/oracle/oradata/prim/stby04.log’ size 50m;

SQL> ALTER DATABASE ADD STANDBY LOGFILE GROUP 5   ‘/u01/app/oracle/oradata/white/stby04.log’ size 50m;

 Step #3:

On Primary Database Should Create Pfile , to modify it and add parameters .

SQL> CREATE PFILE FROM SPFILE;
OR
SQL> CREATE PFILE=’/initSID’ from spfile;

prim.__db_cache_size=121634816
prim.__java_pool_size=41943040
prim.__large_pool_size=4194304
prim.__shared_pool_size=109051904
prim.__streams_pool_size=0
*.audit_file_dest=’/u01/app/oracle/admin/prim/adump’
*.background_dump_dest=’/u01/app/oracle/admin/prim/bdump’
*.compatible=’10.2.0.1.0′
*.control_files=’/u01/app/oracle/oradata/prim/control01.ctl’,’/u01/app/oracle/oradata/prim/control02.ctl’,’/u01/app/oracle/oradata/prim/control03.ctl’
*.core_dump_dest=’/u01/app/oracle/admin/prim/cdump’
*.db_block_size=8192
*.db_domain=”
*.db_file_multiblock_read_count=16
*.db_name=’prim’
*.db_recovery_file_dest=’/u01/app/oracle/flash_recovery_area’
*.db_recovery_file_dest_size=2147483648
*.dispatchers='(PROTOCOL=TCP) (SERVICE=primXDB)’
*.job_queue_processes=10
*.open_cursors=300
*.pga_aggregate_target=94371840
*.processes=150
*.remote_login_passwordfile=’EXCLUSIVE’
*.sga_target=283115520
*.undo_management=’AUTO’
*.undo_tablespace=’UNDOTBS1′
*.user_dump_dest=’/u01/app/oracle/admin/prim/udump’
db_unique_name=’prim’
LOG_ARCHIVE_CONFIG=’DG_CONFIG=(prim,stdby)’
LOG_ARCHIVE_DEST_1=’LOCATION=/u01/app/oracle/oradata/prim/arch/ VALID_FOR=(ALL_LOGFILES,ALL_ROLES) DB_UNIQUE_NAME=prim’
LOG_ARCHIVE_DEST_2=’SERVICE=stdby LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLES) DB_UNIQUE_NAME=stdby’
LOG_ARCHIVE_DEST_STATE_1=ENABLE
LOG_ARCHIVE_DEST_STATE_2=ENABLE
LOG_ARCHIVE_FORMAT=%t_%s_%r.arc
LOG_ARCHIVE_MAX_PROCESSES=30
FAL_SERVER=stdby
FAL_CLIENT=prim
standby_file_management=auto
db_file_name_convert=’/u01/app/oracle/oradata/stdby/’,’/u01/app/oracle/oradata/prim/’
log_file_name_convert=’/u01/app/oracle/oradata/stdby/’,’/u01/app/oracle/oradata/prim/’

Once you Create and modify pfile you should startup database with it .

SQL > Shutdown immediate 
SQL > Startup nomount pfile=’/u01/initPrim.ora’;
SQL > Alter database mount ;
SQL > alter database open ;
SQL > Create Spfile from pfile = ‘/u01/initPrim.ora’;

Bounce Database again .


Step#4 : Backup Primary Database Using RMAN 

RMAN> backup full database format ‘/u01/rman/%d_%U.bkp’ plus archivelog format ‘/u01/rman/%d_%U.bkp’;

Next, create a standby controlfile backup via RMAN:
RMAN> configure channel device type disk format ‘/u01/rman/%U’;

RMAN> BACKUP CURRENT CONTROLFILE FOR STANDBY;

Move The backupset to Standby Using SCP

scp -r oracle@Primary-Database-ip :/u01/rman oracle@standby-database-ip:/u01/

The primary and standby database location for backup folder must be same.

Steps#5 :  Start Working On Standby Database .

 you should Create standby folders , to make sure No error will be appear .

mkdir -p /u01/app/oracle/oradata/stdby
mkdir -p /u01/app/oracle/oradata/stdby/arch
mkdir -p /u01/app/oracle/admin/stdby
mkdir -p /u01/app/oracle/admin/stdby/adump
mkdir -p /u01/app/oracle/admin/stdby/bdump
mkdir -p /u01/app/oracle/admin/stdby/udump
mkdir -p /u01/app/oracle/flash_recovery_area/PRIM
mkdir -p /u01/app/oracle/flash_recovery_area/PRIM/onlinelog


Step#6: Parameter file for Standby

stdby.__db_cache_size=121634816
stdby.__java_pool_size=41943040
stdby.__large_pool_size=4194304
stdby.__shared_pool_size=109051904
stdby.__streams_pool_size=0
*.audit_file_dest=’/u01/app/oracle/admin/stdby/adump’
*.background_dump_dest=’/u01/app/oracle/admin/stdby/bdump’
*.compatible=’10.2.0.1.0′
*.control_files=’/u01/app/oracle/oradata/stdby/control01.ctl’,’/u01/app/oracle/oradata/stdby/control02.ctl’,’/u01/app/oracle/oradata/stdby/control03.ctl’
*.core_dump_dest=’/u01/app/oracle/admin/stdby/cdump’
*.db_block_size=8192
*.db_domain=”
*.db_file_multiblock_read_count=16
*.db_name=’prim’
*.db_recovery_file_dest=’/u01/app/oracle/flash_recovery_area’
*.db_recovery_file_dest_size=2147483648
*.dispatchers='(PROTOCOL=TCP) (SERVICE=stdbyXDB)’
*.job_queue_processes=10
*.open_cursors=300
*.pga_aggregate_target=94371840
*.processes=150
*.remote_login_passwordfile=’EXCLUSIVE’
*.sga_target=283115520
*.undo_management=’AUTO’
*.undo_tablespace=’UNDOTBS1′
*.user_dump_dest=’/u01/app/oracle/admin/stdby/udump’
db_unique_name=’stdby’
LOG_ARCHIVE_CONFIG=’DG_CONFIG=(prim,stdby)’
LOG_ARCHIVE_DEST_1=’LOCATION=/u01/app/oracle/oradata/stdby/arch/ VALID_FOR=(ALL_LOGFILES,ALL_ROLES) DB_UNIQUE_NAME=stdby’
LOG_ARCHIVE_DEST_2=’SERVICE=prim LGWR ASYNC VALID_FOR=(ONLINE_LOGFILES,PRIMARY_ROLES) DB_UNIQUE_NAME=prim’
LOG_ARCHIVE_DEST_STATE_1=ENABLE
LOG_ARCHIVE_DEST_STATE_2=ENABLE
LOG_ARCHIVE_FORMAT=%t_%s_%r.arc
LOG_ARCHIVE_MAX_PROCESSES=30
FAL_SERVER=’prim’
FAL_CLIENT=’stdby’
standby_file_management=auto
db_file_name_convert=’/u01/app/oracle/oradata/prim/’,’/u01/app/oracle/oradata/stdby/’
log_file_name_convert=’/u01/app/oracle/oradata/prim/’,’/u01/app/oracle/oradata/stdby/’


Step#7:Configure Listener and tnsnames.ora On Both :

On Primary Database :

tnsnames.ora


STDBY =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST =)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = stdby)
    )
  )
PRIM =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = )(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = prim)
    )
  )

Same On Standby , On Standby Databsase Use netca to create listener . and make sure its up
test the connection between both nodes via tnsping m and its should be able to Connect .

Step#8:

on Standby Database

echo “stdby:/u01/app/oracle/product/10.2.0/db_1:N” >> /etc/oratab

export ORACLE_SID=stdby
sqlplus / as sysdba
SQL > startup nomount pfile=’/u01/initSTDBY.ora’;
 SQL > Create Spfile from pfile = ‘/u01/initSTDBY.ora’;

Bounce Database.
SQL > Startup nomount ;
SQL > exit;

export ORACLE_SID=stdby ;
rman target=sys/oracle@prim auxiliary=/

Connection should be like the following :
connected to target database: PRIM (DBID=3603586489) –Prim
connected to auxiliary database: PRIM (not mounted) –Standby

RMAN> DUPLICATE TARGET DATABASE FOR STANDBY NOFILENAMECHECK;

Now We Done Creating Standby Database ,  we will Start Sync :

SQL> alter database recover managed standby database disconnect from session;

 You can Check If everything is up to date with standby , use archive log list on both node to check archive log number .

Thank you
Osama Mustafa

Bounce Standby Database

Posted on by Osama Mustafa in Database
Shutdown Standby Database :

    sqlplus /as sysdba
    alter database recover managed standby database cancel;
    shutdown;
 

Startup Standby Database :

     sqlplus /as sysdba
     startup nomount
     alter database mount standby database
     alter database recover managed standby database disconnect from session;

Thank you
Osama Mustafa

ORA-16024: parameter LOG_ARCHIVE_DEST_1 cannot be parsed

Posted on by Osama Mustafa in Database
ORA-16024: parameter LOG_ARCHIVE_DEST_1 cannot be parsed

Cause:
Missing Space Issue

Solution 
log_archive_dest_1 = ‘LOCATION=/u01/app/oracle/prim/ VALID_FOR=(ALL_LOGFILES,ALL_ROLES)DB_UNIQUE_NAME=prim’

Should be 

log_archive_dest_1 = ‘LOCATION=/u01/app/oracle/prim/ VALID_FOR=(ALL_LOGFILES,ALL_ROLES) DB_UNIQUE_NAME=prim’

Thank you
Osama Mustafa

AWR vs ADDM vs ASH

Posted on by Osama Mustafa in Database
AWR : automatic workload repository

The AWR is used to collect performance statistics including:

  • Wait events used to identify performance problems.
  • Time model statistics indicating the amount of DB time associated with a process from the V$SESS_TIME_MODEL and V$SYS_TIME_MODEL views.
  • Active Session History (ASH) statistics from the V$ACTIVE_SESSION_HISTORY view.
  • Some system and session statistics from the V$SYSSTAT and V$SESSTAT views.
  • Object usage statistics.
  • Resource intensive SQL statements.

I will not get into Details how to generate AWR since i mention it before on my Blog .

 ADDM : automatic database diagnostic monitor

analyzes data in the Automatic Workload Repository (AWR) to identify potential performance bottlenecks.and we use it for the following cases :

  •      CPU bottlenecks
  •      Undersized memory structures
  •      I/O capacity issues
  •      High load SQL statements
  •      RAC specific issues
  •      Database configuration issues
  •      Also provides recommendations on hardware changes, database configuration & schema changes.

Generate ADDM  :

  • Login to SQL
  • @$ORACLE_HOME/rdbms/admin/addmrpt.sql
  •  enter system password when you asked for .
  • Specify a begin_snap from the list and press Enter.
  • Specify the end_snap from the list and press Enter.
  •  Report Name

ASH : Active Session History 

statistics from the in-memory performance monitoring tables also used to track session activity and simplify performance tuning.

ASH reports Give the following information :

  • Top User Events (frequent wait events)
  • Details to the wait events
  • Top Queries
  • Top Sessions
  • Top Blocking Sessions
  • Top DB Object.
  • Activity Over Time

 Generate ASH reports :

The Best way to do that using OEM.  (Enterprise manager).

Thank you
Osama Mustafa

ORA-01438 Which Column

Posted on by Osama Mustafa in Database

ORA-01438: value larger than specified precision allowed for this column

You will receive this error while trying to insert big Value In Column with Specific Range , But How Could You know Which Column is it i will some hint that could help you to do that :

Hint #1 :

1-ORA-01438  : For Numeric Value
2-ORA-12899  : For Varchar2 Value

Hint #2 :

Enable Audit On know which One of these Column caused the error

SQL > Create table test as select * from scott.dept 

SQL> desc dept
 Name                                Null?    Type
 ----------------------------------- -------- ------------------------
 DEPTNO                              NOT NULL NUMBER(2)
 DNAME                                        VARCHAR2(14)
 LOC                                          VARCHAR2(13)
 
SQL> audit insert on Osama.test whenever not successful;
 
Audit succeeded.
 
SQL> insert into osama.test values(2000,'Osama','Osama');
insert into scott.dept values(2000,'osama','Osama')
                              *
ERROR at line 1:
ORA-01438: value larger than specified precision allowed for this
column
 
 
SQL> select sql_text,returncode from dba_audit_trail
  2  where owner='OSAMA' and obj_name='TEST';
 
SQL_TEXT
----------------------------------------------------------------------
RETURNCODE
----------
insert into scott.dept values(2000,'Osama','Osama')
      1438

 Hint #3 :

Enable Tracing Level 1438

SQL > conn osama/osama ;
SQL> create table test as select * from scott.dept ;
 
SQL> select * from test ;
 
    DEPTNO DNAME          LOC
---------- -------------- -------------
        10 ACCOUNTING     NEW YORK
        20 RESEARCH       DALLAS
        30 SALES          CHICAGO
        40 OPERATIONS     BOSTON
 
 
SQL> alter system set events='1438 trace name Errorstack forever,level 10';
 
 
SQL> insert into test values (100000000000000000,'osama','JOR');                         
insert into test values (100000000000000000,'osama','JOR')
                         *
ERROR at line 1:
ORA-01438: value larger than specified precision allowed for this column
 
In Trace File :
 
ORA-01438: value larger than specified precision allowed for this column
Current SQL statement for this session:
insert into test values (100000000000000000,'osama','JOR')

Thank you
Osama Mustafa