How to Create TEMPORARY tablespace and drop existing temporary tablespace in oracle 11g/12c

1. Create Temporary Tablespace Temp

create temporary tablespace temp2 tempfile '/mnt/mnt04/oradata/temp01.dbf'size 2000M; 

2. Move Default Database temp tablespace

ALTER DATABASE DEFAULT TEMPORARY TABLESPACE temp2;

3. Make sure No sessions are using your Old Temp (TEMP) tablespace

   a.  Find Session Number from V$SORT_USAGE: 
       SELECT USERNAME, SESSION_NUM, SESSION_ADDR FROM V$SORT_USAGE; 

SQL> SELECT USERNAME, SESSION_NUM, SESSION_ADDR FROM V$SORT_USAGE;

USERNAME                       SESSION_NUM        SESSION_ADDR
----------------------------------------------------------------------------- 
SYS                                       45684           0000000CE2EA7CC8

   b.  Find Session ID from V$SESSION:

       If the resultset contains any tows then your next step will be to find the SID from the V$SESSION view. You can find session id by using SESSION_NUM or SESSION_ADDR from previous resultset.

       SELECT SID, SERIAL#, STATUS FROM V$SESSION WHERE SERIAL#=SESSION_NUM;
       OR
       SELECT SID, SERIAL#, STATUS FROM V$SESSION WHERE SADDR=SESSION_ADDR; 
OR
SQL> SELECT b.tablespace,b.segfile#,b.segblk#,b.blocks,a.sid,a.serial#,
a.username,a.osuser, a.status
FROM v$session a,v$sort_usage b
WHERE a.saddr = b.session_addr;

c.  Kill Session:

Provide above inputs to following query, and kill session’s.
SQL> alter system kill session 'SID_NUMBER, SERIAL#NUMBER';
For example:
SQL> alter system kill session '633,45684';

4. Drop TEMP tablespace

drop tablespace TEMP including contents and datafiles;

5. Recreate Tablespace Temp

CREATE TEMPORARY TABLESPACE TEMP TEMPFILE  '/mnt/mnt04/oradata/temp_01.dbf' SIZE 1G AUTOEXTEND ON NEXT 1G MAXSIZE 32767M;

6. Move Tablespace Temp, back to new temp tablespace

ALTER DATABASE DEFAULT TEMPORARY TABLESPACE TEMP;

7. Drop temporary for tablespace temp

DROP TABLESPACE temp2 INCLUDING CONTENTS AND DATAFILES;

No need to do shutdown when drop temp tablespace and the recreate it. If something happen with temp tablespaces e.g. : crash, corrupt, etc. Oracle database will ignore the error, but DML (insert,update,delete) and SELECT Query will suffer.

Cleaning Oracle SYSAUX Tablespace Usage - SYSAUX tablespace is 97.51%

Normally the SYSAUX tablespace is more or less stable so it would be smart to check what is eating the space in there. Connected as a DBA user, run the script ${ORACLE_HOME}/rdbms/admin/utlsyxsz to get the current usage of the SYSAUX tablespace and see how it will grow when you change certain parameters for which you are asked to enter values.

 
OR

select 
   * 
from 
   (select 
      owner,segment_name||'~'||partition_name segment_name,bytes/(1024*1024) meg 
   from 
      dba_segments 
      where tablespace_name = 'SYSAUX' 
   order by 
      blocks desc);

In my case, below 1  occupying most of the space :-

1. SM/AWRSM/AWR — It refers to Automatic Workload Repository.Data in this section is retained for a certain amount of time (default 8 days). Setting can be checked through DBA_HIST_WR_CONTROL.

Retrieve the oldest and latest AWR snapshot

SELECTsnap_id, begin_interval_time, end_interval_timeFROMSYS.WRM$_SNAPSHOTWHEREsnap_id = ( SELECT MIN (snap_id) FROM SYS.WRM$_SNAPSHOT)UNIONSELECTsnap_id, begin_interval_time, end_interval_timeFROMSYS.WRM$_SNAPSHOTWHEREsnap_id = ( SELECT MAX (snap_id) FROM SYS.WRM$_SNAPSHOT)/

Now use the dbms_workload_repository package to remove the AWR snapshots.

BEGINdbms_workload_repository.drop_snapshot_range(low_snap_id => 7521, high_snap_id=>7888);END;/

Speed up ‘removal’ of old AWR reports

@#$%^&*()_ removing the entries takes ages and fails on undo errors … Metalink note Doc ID: 852028.1 states that I can safely remove the AWR metadata tables and recreate them.If none of the above suits as everything is set proper then consider clean up and rebuild AWR repository to clear all the space.

SQL> connect / as sysdba 
SQL> @?/rdbms/admin/catnoawr.sql 
SQL> @?/rdbms/admin/catawrtb.sql

Reference :-WRH$_ACTIVE_SESSION_HISTORY Does Not Get Purged Based Upon the Retention Policy (Doc ID 387914.1)Suggestions if Your SYSAUX Tablespace Grows Rapidly or Too Large (Doc ID 1292724.1)

ORA-28040: No matching authentication protocol

When connecting to 10g ,11g or 12c databases using a  JDBC thin driver , fails with following errors:

- The Network Adapter could not establish the connection

- ORA-28040: No matching authentication protocol

This happens because you are using a non compatible version of JDBC driver.To resolve this issue, make sure that you are using the latest version of Oracle JDBC driver, if not use JDBC 12c or higher versions. 

Current Interoperability Support Situation

The matrix below summarizes client and server combinations that are supported for the most commonly used product versions. 

ORA-20011: Approximate NDV failed: ORA-29913: error in executing ODCIEXTTABLEOPEN callout

ORA-20011: Approximate NDV failed: ORA-29913: error in executing ODCIEXTTABLEOPEN callout

KUP-11024: This external table can only be accessed from within a Data Pump job.

Alert Log details: 

Trace file details:

Cause:

The primary cause of this issue is that an external table existed at some point in time but does not now. However, the database still believes the table exists since the dictionary information about the object has not been modified to reflect the change. When DBMS_STATS is run against the table in question, it makes a call out to the external table which fails because the object is not there.

There are many reasons that an external table may not exist including:

• - Temporary Datapump external tables have not been cleaned up properly. The dictionary information should have been dropped when the DataPump jobs completed.
• - An OS file for an External table has been removed without clearing up the corresponding data dictionary information. 
• Solution:
• Essentially the solution to this issue is to clean up the orphaned dictionary entries.
• SELECT owner_name, job_name, operation, job_mode, state, attached_sessions FROM dba_datapump_jobs WHERE job_name NOT LIKE 'BIN$%' ORDER BY 1,2;
• or 
• select OWNER,OBJECT_NAME,OBJECT_TYPE, status,
  to_char(CREATED,'dd-mon-yyyy hh24:mi:ss') created
  ,to_char(LAST_DDL_TIME , 'dd-mon-yyyy hh24:mi:ss') last_ddl_time
  from dba_objects
  where object_name like 'ET$%'
  /
  
  select owner, TABLE_NAME, DEFAULT_DIRECTORY_NAME, ACCESS_TYPE
  from dba_external_tables
  order by 1,2
  /
• 
  Drop external temporary table
• 
  Ref. Doc: ID 1274653.1
• 
  

Calculate UNDO_RETENTION for given UNDO Tabespace

UNDO_RETENTION is a parameter in the init.ora initialization parameters file that specifies the time period in seconds for which a system retains undo data for committed transactions. The flashback query can go upto the point of time specified as a value in the UNDO_RETENTION parameter.

Optimal Undo Retention =
           Actual Undo Size / (DB_BLOCK_SIZE × UNDO_BLOCK_REP_ESC)

Actual Undo Size

SELECT SUM(a.bytes) "UNDO_SIZE"
FROM v$datafile a,
       v$tablespace b,
       dba_tablespaces c
WHERE c.contents = 'UNDO'
   AND c.status = 'ONLINE'
   AND b.name = c.tablespace_name
   AND a.ts# = b.ts#;

Undo Blocks per Second

SELECT MAX(undoblks/((end_time-begin_time)*3600*24)) "UNDO_BLOCK_PER_SEC"
FROM v$undostat;

DB Block Size

SELECT TO_NUMBER(value) "DB_BLOCK_SIZE [KByte]"
FROM v$parameter
WHERE name = 'db_block_size';

Optimal Undo Retention Calculation

Formula:
Optimal Undo Retention = 
           Actual Undo Size / (DB_BLOCK_SIZE × UNDO_BLOCK_REP_ESC)

Using Inline Views, you can do all calculation in one query

SQL Code:
SELECT d.undo_size/(1024*1024) "ACTUAL UNDO SIZE [MByte]",
    SUBSTR(e.value,1,25)    "UNDO RETENTION [Sec]",
    ROUND((d.undo_size / (to_number(f.value) *
    g.undo_block_per_sec)))"OPTIMAL UNDO RETENTION [Sec]"
  FROM (
       SELECT SUM(a.bytes) undo_size
          FROM v$datafile a,
               v$tablespace b,
               dba_tablespaces c
         WHERE c.contents = 'UNDO'
           AND c.status = 'ONLINE'
           AND b.name = c.tablespace_name
           AND a.ts# = b.ts#
       ) d,
       v$parameter e,
       v$parameter f,
       (
       SELECT MAX(undoblks/((end_time-begin_time)*3600*24))undo_block_per_sec
       FROM v$undostat
       ) g
WHERE e.name = 'undo_retention'
  AND f.name = 'db_block_size'

Calculate Needed UNDO Size for given Database Activity

If you are not limited by disk space, then it would be better to choose the UNDO_RETENTION time that is best for you (for FLASHBACK, etc.). Allocate the appropriate size to the UNDO tablespace according to the database activity:

Formula:
Undo Size = Optimal Undo Retention × DB_BLOCK_SIZE × UNDO_BLOCK_REP_ESC
Using Inline Views, you can do all calculation in one query

SQL Code:
SELECT d.undo_size/(1024*1024) "ACTUAL UNDO SIZE [MByte]",
       SUBSTR(e.value,1,25) "UNDO RETENTION [Sec]",
       (TO_NUMBER(e.value) * TO_NUMBER(f.value) *
       g.undo_block_per_sec) / (1024*1024)
      "NEEDED UNDO SIZE [MByte]"
  FROM (
       SELECT SUM(a.bytes) undo_size
         FROM v$datafile a,
              v$tablespace b,
              dba_tablespaces c
        WHERE c.contents = 'UNDO'
          AND c.status = 'ONLINE'
          AND b.name = c.tablespace_name
          AND a.ts# = b.ts#
       ) d,
      v$parameter e,
      v$parameter f,
       (
       SELECT MAX(undoblks/((end_time-begin_time)*3600*24))
         undo_block_per_sec
         FROM v$undostat
       ) g
 WHERE e.name = 'undo_retention'
  AND f.name = 'db_block_size'

Top 99 Responsibilities of a DBA

Database Architecture Duties

1. Planning for the database's future storage requirements
2. Defining database availability and fault management architecture
3. Defining and creating environments for development and new release installation
4. Creating physical database storage structures after developers have designed an application
5. Constructing the database
6. Determining and setting the size and physical locations of datafiles
7. Evaluating new hardware and software purchase
8. Researching, testing, and recommending tools for Oracle development, modeling, database administration, and backup and recovery implementation, as well as planning for the future
9. Providing database design and implementation
10. Understanding and employing the optimal flexible architecture to ease administration, allow flexibility in managing I/O, and to increase the capability to scale the system
11. Working with application developers to determine and define proper partitioning

Backup and Recovery

12. Determining and implementing the backup/recovery plan for each database while in development and as the application moves through test and onto production
13. Establishing and maintaining sound backup and recovery policies and procedures
14. Having knowledge and practice of Oracle backup and recovery scenarios
15. Performing Oracle cold backups when the database is shut down to ensure consistency of the data
16. Performing Oracle hot backups while the database is operational
17. Performing Oracle import/export as a method of recovering data or individual objects
18. Providing retention of data to satisfy legal responsibilities of the company
19. Restoring database services for disaster recovery
20. Recovering the database in the event of a hardware or software failure
21. Using partitioning and transportable tablespaces to reduce downtime, when appropriate

Maintenance and Daily Tasks

22. Providing adjustment and configuration management of INIT.ORA
23. Adjusting extent size of rapidly growing tables and indexes
24. Administering database-management software and related utilities
25. Automating database startup and shutdown
26. Automating repetitive operations
27. Determining and setting critical thresholds for disk, tablespaces, extents, and fragmentation
28. Enrolling new users while maintaining system security
29. Filtering database alarm and alert information
30. Installing, configuring, and upgrading Oracle server software and related products installation
31. Logging Technical Action Reports (TARs); applying patches
32. Maintaining the "Database Administrator's Handbook"
33. Maintaining an ongoing configuration for database links to other databases
34. Maintaining archived Oracle data
35. Managing contractual agreements with providers of database-management software
36. Managing service level agreements with Oracle consultants or vendors
37. Monitoring and advising management on licensing issues while ensuring compliance with Oracle license agreements
38. Monitoring and coordinating the update of the database recovery plan with the site's disaster recovery plan
39. Monitoring and optimizing the performance of the database
40. Monitoring rollback segment and temporary tablespace use
41. Monitoring the status of database instances
42. Performing housekeeping tasks as required; purging old files from the Oracle database
43. Performing database troubleshooting
44. Performing modifications of the database structure from information provided by application developers
45. Performing monthly and annual performance reports for trend analysis and capacity planning
46. Installing new and maintaining existing client configurations
47. Performing ongoing configuration management
48. Performing ongoing Oracle security management
49. Performing routine audits of user and developer accounts
50. Performing translation of developer modeled designs for managing data into physical implementation
51. Performing correlation of database errors, alerts, and events
52. Planning and coordinating the testing of the new database, software, and application releases
53. Providing a focal point on calls to Oracle for technical support
54. Working as part of a team and providing 24x7 support when required

Methodology and Business Process

55. Coordinating and executing database upgrades
56. Coordinating upgrades of system software products to resolve any Oracle/operating system issues/conflicts
57. Creating error and alert processes and procedures
58. Creating standard entry formats for SQLNet files
59. Creating processes and procedures for functional and stress testing of database applications
60. Creating processes and procedures of application transport from DEV, to TEST, to PROD
61. Defining and maintaining database standards for the organization to ensure consistency in database creation
62. Defining database standards and procedures to cover the instance parameters, object sizing, storage, and naming. The procedures define the process for install/upgrade, corporate database requirements, security, backup/recovery, applications environment, source code control, change control, naming conventions, and table/index creation.
63. Defining the database service levels necessary for application availability
64. Defining methodology tasks for database software integration
65. Defining a methodology for developing and improving business applications
66. Creating a process to determine whether a new release is "stable" enough to be placed on the development system
67. Developing data-conversion processes for customization, testing, and production
68. Developing database test plans
69. Developing database administration procedures and responsibilities for production systems
70. Developing production migration procedures
71. Establishing and providing schema definitions, as well as tablespace, table, constraint, trigger, package, procedure, and index naming conventions
72. Facilitating design sessions for requirements gathering and defining system requirements
73. Providing database problem reporting, management, and resolution
74. Providing final approval for all technical architecture components that manage and exchange data, including database management software, serve hardware, data distribution management software, server hardware, data distribution management software, transaction processing monitors, and connecting client applications software
75. Providing processes for the setup of new database environments
76. Providing risk and impact analysis of maintenance or new releases of code
77. Providing standards and methods for database software purchasing
78. Providing standards and naming conventions
79. Handling multiple projects and deadlines

Education and Training

80. Attending training classes and user group conferences
81. Evaluating Oracle features and Oracle-related products
82. Understanding the Oracle database, related utilities, and tools
83. Understanding the underlying operating system as well as the design of the physical database
84. Understanding Oracle data integrity
85. Knowing the organization's applications and how they map to the business requirements
86. Knowing how Oracle acquires and manages resources
87. Knowing enough about the Oracle tool's normal functional behavior to be able to determine whether a problem lies with the tool or the database
88. Processing sound knowledge in database and system performance tuning
89. Providing in-house technical consulting and training
90. Staying abreast of the most current release of Oracle software and compatibility issues
91. Subscribing to database trade journals and web sources

Communication

92. Interfacing with vendors
93. Disseminating Oracle information to the developers, users, and staff
94. Training application developers to understand and use Oracle concepts, techniques, and tools that model and access managed data
95. Assisting developers with database design issues and problem resolutions, including how to run and understand the output from both TKProf and the Explain Plan utilities
96. Training interim DBAs and junior-level DBAs

Documentation

97. Creating and maintaining a database operations handbook for frequently performed tasks
98. Defining standards for database documentation
99. Creating documentation of the database environment

Source - http://appsdbaportal.blogspot.com/2009/04/top-99-responsibilities-of-dba.html

Meaning of Oracle “I” “G” and “C”

Meaning of “I” and “G” in Oracle and the Release format number of version

Meaning of I in Oracle:

The Oracle version starting of I. The starting in 1999 with version 6i, 8i and 9i, I signify “Internet” means stands for “Internet” and Oracle added the “I” to the version name to reflect support for the Internet with its built-in Java Virtual Machine (JVM). Oracle 9i added more support for XML in 2001.

Meaning of G in Oracle:

The starting in 2003 with version 10g and 11g, G signifies “Grid Computing” with the release of Oracle10g in 2003. Oracle 10g was introduced with emphasis on the “g” for grid computing, which enables clusters of low-cost, industry standard servers to be treated as a single unit. Upgrade Enterprise Manager 10g Grid Control Release 4 (10.2.0.4.0) or higher to Enterprise Manager 11g Grid Control Release 1 (11.1.0.1.0).

Meaning of C in Oracle:

In the Oracle Database 12c the "c" stands for "cloud". In addition to many new features, this new version of the Oracle Database implements a multitenant architecture, which enables the creation of pluggable databases (PDBs) in a multitenant container database (CDB). The Oracle Database 12c is a high-performance, enterprise-class database. Oracle released Oracle Database 12c into general availability July 1, 2013. According to Oracle, this is "the first database designed for the cloud." Oracle Database 12c also introduces 500 new features to the database, most notably pluggable databases and multitenant architecture. The Oracle Database 12c release 12.0.1.2 also features the Oracle Database 12c In-Memory, an optional add-on that provides in-memory capabilities. The in-memory option makes Oracle Database 12c the first Oracle database to offer real-time analytics.