The Real Scoop on Migrating from Oracle Databases

© 2013 EnterpriseDB Corporation. All rights reserved. 1

[email protected] 2013-10-30

The Real Scoop on Migrating from Oracle Databases


Agenda •  Company Overview •  What is Postgres Plus Advanced Server? •  What do we mean by ‘Oracle Compatibility’?

•  What does this mean to you? •  Migration Methodology •  How to Migrate

•  Handling migration issues •  How EnterpriseDB can help •  Summary

•  Some common questions answered •  Q&A


Providing enterprises with the cost-performance benefits of Postgres by offering the products, resources, support and dependability required for high-level commercial applications.!• 140+ employees

• 2,500+ customers across all market segments

• Global presence with offices in North America, Europe, Asia

• Fast growing: 60%+ YOY sales growth in 2012, 80%+ YOY 2013

• Strong financial banking:

© 2013 EnterpriseDB. All rights reserved.


New Gartner ODBMS Magic Quadrant

Gartner Comments:

•  Community leadership — EnterpriseDB is the primary contributor to the PostgreSQL community and is responsible for many new features of PostgreSQL, including JSON.

•  Functionality — The functionality of EnterpriseDB's Postgres Plus has increased greatly, and with the Oracle Compatibility Feature is now more than sufficient to run both mission-critical and non-mission-critical applications.

•  Stability and compatibility — References specifically call out compatibility with Oracle, the stability of the DBMS and product support as strengths.


Synchronized with and contributing to the PostgreSQL community

Postgres Plus: A Super-Set of Features


What Is Postgres Plus Advanced Server?

u  Superset of community PostgreSQL

u  10th generation of Oracle compatibility, since 2005

u  World-class security add-ons u  Performance that rivals any other

proprietary RDBMS u  Enterprise-class developer and

DBA tools u  Installation, performance tuning,

and maintenance services u  Software indemnification


Oracle Compatibility - Goals

•  Run applications written for Oracle virtually unchanged

•  No need to re-train Oracle DBAs and developers

•  Support for SQL, PL/SQL, OCI and Pro*C

•  Replication for easy sharing of data

•  Dramatic Cost Savings

•  No Vendor Lock-in


Compatibility means: •  SQL extension support

−  Decode, NVL, Substr, NVL2 −  Date/time functions: add_months, extract, next_day

•  PL/SQL support −  REF Cursors, Implicit and explicit cursors −  Looping, variable declarations, conditional statements −  Collections: Associative Arrays, Varrays, Nested tables −  Bulk binding −  Named parameters −  User Defined Exceptions −  Explicit Transaction Control

−  within a stored procedure −  (not supported by PostgreSQL)


Compatibility means: (cont.) •  Features

−  Packages −  Stored procedures −  Functions −  Triggers −  Hints −  Database Links −  Hierarchical Queries −  Materialized view (foundation) (*1) −  Synonyms – Public and Private −  Sequences −  Rownum −  Object types

−  Create type … as object, … as table, …as varray −  Constructor and collection methods

−  Users/Roles −  Dynamic SQL *1 – PPAS 9.3


Compatibility means: (cont.) •  Data Types

Integer, number, char, double precision, float, varchar2, blob, clob, xmltype, rowid

•  Built-in Packages DBMS_:

SQL, RLS, LOB, JOB, PIPE, ALERT, OUTPUT, UTILITY, PROFILER RANDOM, LOCK, CRYPTO, SCHEDULER, MVIEW (*1)

UTL_: FILE, MAIL, SMTP, ENCODE, TCP HTTP, URL (*1)

REGEXP_: INSTR, SUBSTR, COUNT (*1)

•  Oracle-like Data Dictionary −  ALL_, DBA_, USER_ views −  Most commonly accessed views

*1 – PPAS 9.3


Compatibility means: (cont.) •  Diagnostics - DRITA

−  System and session waits −  Not exposed in PostgreSQL −  Part of Advanced Server

−  Statspack like reporting

•  Tools −  EDB*Plus (SQL*Plus look-a-like) −  EDB*Loader (SQL*Loader equivalent) −  EDB*Wrap (similar to the PL/SQL wrapper)

*1 – PPAS 9.3


Partitioning in PPAS v9.3

76 times Faster!

0

10

20

30

40

50

60

70

80

250 500 1000

Impr

ovem

ent F

acto

r

Number of Table Partitions

•  Oracle syntax for partitioning (create, add, exchange, split, …) •  Postgres Plus Advanced Server is up to 76 times faster for data

retrieval than PostgreSQL 9.3 or PPAS 9.2 (Partition pruning, and inserts) •  The greater the number partitions, the greater the performance benefits

PPAS 9.2 PostgreSQL 9.3

PPAS 9.3

Partitioning Performance: PPAS 9.3 v. PostgreSQL 9.3 v. PPAS 9.2


Migration Example


Database Migration Toolkit •  Online Migration Toolkit enables point and click migration from

Oracle

•  Automatically Migrates:

u  Data u  Schemas u  Stored Procedures u  Triggers u  Functions

u  Sequences u  Packages u  Views u  Database Links u  Synonyms


Oracle Compatibility & Migration Strategies Strategy Benefits

Develop/Deploy New LOB Applications

§ Significant cost savings for non mission critical systems

§ Leverages all existing Oracle skills § Very low risk

Deploy Postgres Plus as Oracle

Replication Server

§ Significant cost savings § Leverages Postgres Plus Replication Server § Leverages all existing Oracle skills § Improves transaction and query performance

Migrate non Mission Critical Oracle Apps to

Postgres Plus

§ Significant cost savings § Leverages all existing Oracle skills § Very low risk

Migrate Mission Critical Oracle Apps to Postgres Plus

§ Biggest cost savings § Leverages all existing Oracle skills § Greatest deployment flexibility


Multi-phase Migration Process u  Phase I – Planning

•  Determine what application to migrate"–  Home grown applications!–  Java, C!–  Packaged applications that support multiple databases!–  Support JDBC, ODBC"

•  Once candidate applications are chosen, sign up for OMA"•  Oracle Migration Assessment (OMA) Identifies:"

–  Possible migration issues!–  Gives time estimate to migrate system"

•  Establish migration team:"–  Need source system knowledgeable resource!–  Need target system knowledgeable resource"

•  Establish project plan with milestones


Multi-phase Migration Process

•  Phase II – Prepare Environment −  Obtain and install necessary software −  Establish connectivity between systems

−  Copy the Oracle JDBC jar file to jre/lib/ext directory in Postgres Plus Advanced Server Installation

•  Phase III – Migrate Schema −  Use Migration Toolkit in schema only mode −  Resolve issues here before going to next phase

•  Phase IV – Migrate Data −  Use command line MTK

−  Use –copyViaDBLinkOra −  Uses OCI to connect to Oracle

−  Use parallel threads −  Use dblink_ora_copy function directly to bypass logging −  Export Oracle data to flat files, load using EDB*Loader


Multi-phase Migration Process

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•  Phase V – Port Application −  Change connection information −  Recompile /Link application (OCI or Pro*C)

•  Phase VI – Test −  Verify application functionality −  Address issues −  Test performance −  Tune

•  Phase VII Integration −  Establish co-existence strategy −  Setup database links to other databases −  Setup replication between Oracle or SQL Server and Postgres

Plus Advanced Server

•  Phase VIII – Rollout −  System becomes production


Work Products

Phase I Oracle Migration Assessment

•  Detailed OMA Analysis Report

•  List of known workarounds

•  Technology risks

•  Compatibility Score

•  Proposed migration approach including skills requirements, training, architecture support, developer subscription, and development resources


Phase I Setup MTK Environment •  Establish connectivity

−  Copy Oracle JDBC jar file to Postgres Plus Advanced Server install

cp /usr/lib/oracle/xe/app/oracle/product/11.2.0/server/jdbc/lib/ojdbc14.jar /opt/PostgresPlus/9.2AS/jre/lib/ext

−  Edit the toolkit.properties file to contain Oracle and Postgres Plus Advanced

Server connection information:

SRC_DB_URL=jdbc:oracle:thin:@localhost:1521:xe SRC_DB_USER=system SRC_DB_PASSWORD=manager TARGET_DB_URL=jdbc:edb://localhost:5999/demo TARGET_DB_USER=demo

TARGET_DB_PASSWORD=manager


Phase II Oracle Migration Toolkit •  *** Checking for Migration Issues *** •  Object Type Type Count •  ------------------------------------------------------------------------------- •  TRIGGER Count 0 •  SOURCE Package 0 •  SOURCE Syntax - Exception 0 •  SOURCE Function 789 •  SOURCE Syntax - Object 0 •  SOURCE Syntax - Other 792 •  SOURCE Syntax - Hints 282 •  SOURCE Syntax - Exp Trans Ctl 730 •  SOURCE Total Count 2623 •  COLLECTION Count 1 •  VARRAY Count 0 •  DIMENSION Count 0 •  JOB Count 0 •  MATERIALIZED VIEW Count 0 •  RESOURCE MGR Count 0 •  POLICY Count 9 •  PROFILE Count 6 •  SUMMARY Possible Migration Issues 2775


Phase III Migrate Schema

Use MTK in schema only mode: [enterprisedb@localhost bin]$ ./runMTK.sh -schemaOnly hr Source database connectivity info... conn =jdbc:oracle:thin:@localhost:1521:xe user =system password=****** Target database connectivity info... conn =jdbc:edb://localhost:5999/demo user =demo password=****** Connecting with source Oracle database server... Connecting with target EnterpriseDB database server... Importing redwood schema hr... Creating Schema...hr Creating Object Type: NUMLIST Creating Sequence: EMPLOYEES_SEQ Creating Tables... Creating Table: EMPLOYEES


Phase III Migrate Schema con’t ******************** Migration Summary ******************** Object Types: 9 out of 9 Sequences: 3 out of 3 Tables: 49 out of 53 Constraints: 39 out of 40 Procedures: 7 out of 7 Functions: 3 out of 3 Packages: 3 out of 3 Total objects: 139 Successful count: 134 Failure count: 5 List of failed objects ====================== Tables -------------------- 1. HR.BFTEST 2. HR.TESTBD 3. HR.TESTBF 4. HR.TESTCNTXT


Phase III Migrate Schema con’t

•  Migration logs stored in user’s home directory : /home/enterprisedb/.enterprisedb/migration-toolkit/logs

•  Resolve issues: Error Creating Table TESTCNTXT:ERROR: function sys_context(unknown,

unknown) does not exist

Hint: No function matches the given name and argument types. You might need to add explicit type casts.

CAUSE: this table used SYS_CONTEXT(‘USERENV’,’CURRENT_USER’) as a DEFAULT value

RESOLUTION: use CURRENT_USER function instead


Phase III Migrate Schema con’t

•  Migration logs stored in user’s home directory : •  Resolve issues: XMLELEMENT : 35

There is a similar function in Postgres with the same name but the syntax is slightly different.

SELECT xmlelement(name foo, xmlattributes(current_date as bar), 'cont', 'ent'); xmlelement ------------------------------------- <foo bar="2007-01-26">content</foo>


Phase IV Migrate Data

•  Use MTK in data only mode: •  [enterprisedb@localhost bin]$ ./runMTK.sh -dataOnly hr •  Source database connectivity info... •  conn =jdbc:oracle:thin:@localhost:1521:xe •  user =system •  password=****** •  Target database connectivity info... •  conn =jdbc:edb://localhost:5999/demo •  user =demo •  password=****** •  Connecting with source Oracle database server... •  Connecting with target EnterpriseDB database server... •  Importing redwood schema hr... •  Loading Table Data in 8 MB batches... •  Loading Table: AGES ... •  [AGES] Migrated 1 rows. •  [AGES] Table Data Load Summary: Total Time(s): 0.467 Total Rows: 1 •  Loading Table: DEPARTMENTS ...


Phase V Port the Application §  Change Application Connection method

§  Java application =

§  Old connection syntax:

Class.forName("oracle.jdbc.driver.OracleDriver");

Connection con = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:xe”,”hrapp”,”manager”);

§  New connection syntax:

Class.forName("com.edb.Driver");

Connection con = DriverManager.getConnection("jdbc:edb://localhost:5444/edb",

“hrapp",“manager");


Handling Issues •  Not all migrations are error free

−  Migration log will contain all errors

•  Some common issues: −  Column delimiter chosen is in column data

−  Causes ‘Extra data found’ error −  Resolve by using different delimiter

•  Oracle built-in package does not exist −  DBMS_AQ – we use solutions like ActiveMQ, MQSeries or Tibco

−  Or own code. Enqueue and dequeue procedures are fairly easy to code −  xDB Replication Server can also be used since based on pub/sub architecture −  DBMS_LOCK.sleep – use pg_sleep function instead

•  Oracle feature not supported −  MERGE command not supported

−  Can be rewritten to use INSERT and UPDATE with checks −  Index Organized Tables

−  Cluster a table using CLUSTER command for same read performance gain


Handling Issues (continued) •  Database Links

−  Migrated over by tool but password is invalid −  This is because Oracle hides the password −  Resolve by dropping and recreating −  Or by specifying a password to use when running the MTK

−  runMTK -allDBLinks LINK_NAME1=abc,LINK_NAME2=xyz HR

•  Data Movement – performance −  Migration toolkit connects via jdbc −  Large datasets are slow to move −  Use database link functionality instead

−  Dblink_ora_copy – EnterpriseDB method to copy data from Oracle over OCI −  Much faster

−  OR extract data from Oracle to csv files, load using edbldr


Tuning Recommendations

•  Use DynaTune −  Dynamically adjusts database configuration based on available resources −  Set via edb_dynatune parameter

−  Values 0 – 100 corresponding to % of machines to use

•  Remember to analyze database −  Use Analyze command

•  Oracle Hints supported −  No need to remove from embedded SQL


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How EnterpriseDB Can Help


Oracle Migration Assessment •  Paid for service from EnterpriseDB

•  What is it? −  Pre-analysis interview −  Analysis of Oracle schemas to be migrated −  Finds possible migration issues

−  Unsupported Features −  Unsupported Syntax −  Implementation Differences

−  Findings documented in final report −  Post analysis discussions to review findings

•  Migration feasibility score assigned (1 – 10)

http://www.enterprisedb.com/solutions/oracle-migration-assessment


Professional services for your migration Assist after the OMA

•  Plan rollout

•  Migration the Schema and Stored procedures (OMF next)

•  Migrate the data (once, 2x,… minimal down time)

•  Training

•  Port and test application(s) (typically customer)

•  DBA and application coaching/support

•  Support contract

•  Remote DBA


Oracle Migration Factory Core Services •  Customer provides data-less Oracle export of database

•  Migrate the database(s) to Postgres Plus Advanced Server −  Resolve any issues −  Implement workarounds for missing or different functionality −  Perform sanity checking of unit functionality

−  Requires input/output from customer on same units in Oracle

•  Document the changes/workarounds

•  Educate Customer on changes/workarounds −  Advise on application level changes needed

•  Return migrated databases to Customer −  Via pg_dump

•  Customer can customize with add on options


Oracle Migration Factory Add-ons •  Setup and Migrate test system

−  Installation of Postgres Plus Advanced Server on Customer server −  Import of migrated database to Postgres Plus Advanced Server −  Migration of test data from a test Oracle system

•  Application Functional Testing −  Provide assistance in connecting application to database −  Provide assistance in functional testing of application −  Resolve functional testing issues

•  Performance Tuning of Migrated System

•  Production Migration Setup −  Install Postgres Plus Advanced Server on target production server −  Import migrated database from testing server −  Setup of xDB Replication Server

−  Snapshot process will migrate production Oracle data −  Deltas are captured by xDB triggers −  Once snapshot is done, synchronization is performed


Summary •  Migrations are no longer impossible

•  Compatibility provides −  Lower cost of migrations −  Shorter migration timelines −  Lower risk (you can always go back)

•  EnterpriseDB provides −  Oracle compatibility −  Automated tools to migrate from Oracle −  And others: MySQL, Sybase, SQL Server (data & schema)

•  Migration Expertise for: −  Planning −  Performing migration −  Testing −  Rollout

http://www.enterprisedb.com/solutions/oracle-compatibility


EDB Serves ALL Your Postgres Needs

PostgreSQL Postgres Plus

Advanced Server Postgres Plus Cloud


47

Some Common Questions Answered


How can I replace RAC for HA?

§  Active/Passive Clustering is proven technology §  Provides fast detection and failover §  No extra database cost


How can I replace DataGuard(Physical)?

Archiver

Disk Storage

Live Server

Instance

Postgres Plus Advanced Server

Disk Storage

Standby Server

(in recovery mode)

Postgres Plus Advanced Server

WAL WAL

pg_standby


How can I replace DataGuard(Logical)?

» Uses WAL for speed and reliability

» Highly cost effective, uses commodity servers

» Excellent HA solution when clustering is not an option

The Real Scoop on Migrating from Oracle Databases

Technology

Transcript of The Real Scoop on Migrating from Oracle Databases