Tales from a Parallel Universe: Using Oracle 11gR2's Edition Based Redefinition in combination with APEX

Tales from a Parallel Universe:Using 11gR2’s Edition Based Redefinitions (in APEX)

Roel Hartman

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EBR and APEX?

Sorry, you can’t do it...

Questions?

John’s suggestion....

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Who am I?

• Oracle since v5, Forms 2.3, Case*Designer etc

• Presenter at UKOUG (3x), OOW (3x), ODTUG (2x)

ROELHARTMAN.BLOGSPOT.COM

No. 3

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Tom Kyte says:

Unplanned Downtime

Planned Downtime

No. 14© Logica 2010. All rights reserved

Planned Downtime

•Application Upgrade• Create objects

• Replace objects

• Drop objects

• Recompilation

The Case

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Keep the Shop open

1. Prepare new Release

2. Cut over

Version 1

Version 2 1

1

2Boo

Randall

Sulley

+ 2

No. 17© Logica 2010. All rights reserved

• Edition

• Schema

• Object Type

• Object Name

Session runs in the context of an Edition

Parallel Universes

SQL> ALTER USER HR ENABLE EDITIONS;

USER ALTERED.

SQL> ALTER USER HR DISABLE EDITIONS;ALTER USER HR DISABLE EDITIONS *ERROR at line 1:ORA-00922: missing or invalid option

SQL>

SQL> select * from all_editions;

EDITION_NAME PARENT_EDITION_NAME USA------------ ------------------- ---ORA$BASE YES

SQL>

SQL> CREATE EDITION HR_RELEASE2 AS CHILD OF ORA$BASE;

Edition created.

SQL> CREATE EDITION OE_RELEASE2 AS CHILD OF ORA$BASE;CREATE EDITION OE_RELEASE2 AS CHILD OF ORA$BASE;*ERROR at line 1:ORA-38807: Implementation restriction: an edition can have only one child

No. 21© Logica 2010. All rights reserved

ORA$BASEHR OE

HR_RELEASE2

OE_RELEASE2

HR’

OE’

One Child – One Parent

No. 22© Logica 2010. All rights reserved

Editionable•PL/SQL Objects

• Packages

• Procedures

• Functions

• Triggers

•Views

•Synonyms

•Types

Not everything is editionable...

Not Editionable•Tables

•Materialized Views

•DB Links

ORA$BASE

HR_RELEASE2

PL/SQL (A)

PL/SQL (B)

Table X Table Y

PL/SQL (A)

PL/SQL (B)

PL/SQL (B’)

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• “Instead-of-table”

•Only one table in the from clause

•No expressions, only columns

•Can have “regular” table triggers

•Same execution plan

Editioning Views are the new tables

•Editioning Views are Editionable....

Editioning View

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No. 26© Logica 2010. All rights reserved

Editioning View

•Data is the same

•View is different

•Depends on your position / edition

ORA$BASE

HR_RELEASE2

PL/SQL (A)

PL/SQL (B)

Table X_t Table Y_t

PL/SQL (A)

PL/SQL (B)

PL/SQL (B’)

Editioning View X

Editioning View Y

Editioning View Y’

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•Old situation : One column NAME

•New situation : FIRST_NAME / LAST_NAME

•Cross Edition Triggers• Forward• Reverse• Only on a Table• Editionable • In the new edition!

How to handle Table changes?

RELEASE 2ORA$BASE

NAME FIRST_NAME LAST_NAME

Session A Session B

RELEASE 3

Session C

Forward CrossEdition

Trigger

Reverse CrossEdition

Trigger

Cross Edition Triggers

“split” “concat”

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Prepare your Application

1Rename

your tables

2Create

editioning views

3Reroute

privileges

4Recreate triggers

5Recompile

PL/SQL

6Apply VPD

policies

Your last Planned Downtime

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•grant use on edition to <user>

•alter database default edition=<x>

•alter session set edition=<x>

•dbms_session.set_edition_deferred( <x> )

• sys.dbms_sys_sql.parse (_as_user)

• sys_context

•SQL*Plus : show edition

Opening up an Edition

SQL> GRANT USE ON EDITION HR_RELEASE2 TO SCOTT;

Grant succeeded.

SQL> CONNECT SCOTT/TIGERConnected.SQL> select sys_context('userenv', 'current_edition_name') current_edition_name from dual;

CURRENT_EDITION_NAME--------------------ORA$BASE

SQL> ALTER SESSION SET EDITION=HR_RELEASE2;

Session altered.

SQL> select sys_context('userenv', 'current_edition_name') current_edition_name from dual;

CURRENT_EDITION_NAME--------------------HR_RELEASE2

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•Rolling back an upgrade

•Retiring an Edition

•Only the root or a leaf

•No objects are inherited (anymore)

•Not currently in use

•Not the DB default edition

•Recompile objects (reuse settings)

Dropping an Edition

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• *_EDITIONS

• *_EDITION_COMMENTS

• *_VIEWS_AE

• *_SOURCE_AE

• *_OBJECTS_AE

• *_ERRORS_AE

• *_EDITIONING_VIEWS_AE

• *_EDITIONING_VIEW_COLS_AE

•DBMS_EDITIONS_UTILITIES.SET_EDITIONING_VIEWS_READ_ONLY

•DBMS_SESSION.SET_EDITION_DEFERRED( <EDITION_NAME> )

New Database Stuff

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EBR and APEX - 1

•ALTER SESSION SET EDITION

•DBMS_SESSION.SET_EDITION_DEFERRED

•Session Pooling

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•dbms_epg.set_dad_attribute('APEX', 'database-edition', 'HR_RELEASE2');

• in dads.conf : PlsqlDatabaseEdition*

•apex_util.set_edition

• sets CURRENT_EDITION

EBR and APEX - 2

Syntax error on line 48 of /home/oracle/OraHome_1/Apache/modplsql/conf/dads.conf:Invalid command 'PlsqlDatabaseEdition', perhaps mis-spelled or defined by a module not included in the server

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•Build on – views on - Editioning Views

•Four (!) -tier architecture

•Edition your Views or PL/SQL Functions

•Use Authorization Schemes

EBR and APEX - 3

Table

Editioning View

(Regular) View

UI / APEX

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EBR and APEX – Cool demo

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SQLDeveloper support

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•Applications never never never access tables

•Application sets the edition

•Alter DAD’s edition (EPG only)!

Be aware!!

•Dropping objects drops inheritance

•No branching

Best Practices

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•Short time

• Long(er) time

•Only for a specific group

•SaaS environment

Parallel Application Versions

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•Different versions in the same schema

•No more planned downtime!

•Ease of maintenance

• Less redo

• Less risk

•So saving $$$

Summary & conclusions

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•Edition-Based Redefinition: Testing Live Application Upgrades (Without Actually Being Live) - Ms Melanie Caffrey

Today at 14:15

Other sessions @UKOUG

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•Tom Kyte column(s) in Oracle Magazine Jan/Feb 2010 (http://www.oracle.com/technology/oramag/oracle/10-jan/o10asktom.html)

•Bryn's Whitepaper "Edition-Based Redefinition a new capability in Oracle Database 11g Release 2 to support online application upgrade". July 2009 (http://www.oracle.com/technology/deploy/availability/pdf/edition_based_redefinition.pdf)

•Documentation in "Oracle Database Advanced Application Developer's Guide 11g Release 2" (http://download.oracle.com/docs/cd/E11882_01/appdev.112/e10471/adfns_editions.htm).

References

Question Time

My blog : http://roelhartman.blogspot.comMy e-mail : [email protected]