goodman understanding the power and pitfalls of ... the power and pitfalls...understanding the power...

1

� San Ramon, CANov 10 -11 2008

� Camp Hill, PANov 17 -18 2008

� Kansas City, MONov 19 -20 2008

Regional Forums

Robert GoodmanSr DBA

Understanding the Power Understanding the Power and Pitfalls of Partitioningand Pitfalls of Partitioning

In V8, 9 and BeyondIn V8, 9 and Beyond

November 10th, 2008 – Session 2

The Power and Pitfalls of PartitioningThe Power and Pitfalls of Partitioning

• Major Points

• Recent major partitioning enhancements

• Overview of major partitioned table concepts

• Good and bad fits

• Implementation options

• Power and pitfalls of options

DB2 Tablespace HistoryDB2 Tablespace History

V1 V2 V3 V4 V5 V6 V7 V8 9 x X+1

Simple

Index Ctrl Partitioned

Table Ctrl Partitioned

Segmented

LOBs

Universal

pureXML

Major Partitioning EnhancementsMajor Partitioning Enhancements

• DB2 V8• Table Based Partitioning

• Multiple Partitioned Indexes

• Clustering Sequence

• Rotate

• DB2 9• Universal (PBG & PBR)

• Clone Tables

• pureXML

• DB2 x• No New Structures

• Enhanced Capabilities

Significant EnhancementsSignificant Enhancements

• Table Controlled Partitioning

• Multiple Partitioned Indexes

• Clustering Index Flexibility

• Rotate Partition

• Universal Table Space

• Clone Tables

• pureXML

Critical AwarenessCritical Awareness

• What Features?

� Rotate

� Clone

• Why?� Unusual behavior

� Physical - logical mapping

� DDL & utility behavior

� Destroy data

� Recovery restrictions

2

Table Controlled PartitioningTable Controlled Partitioning

Table Controlled Partitioning A type of partitioning in which partition boundaries for a partitioned table are controlled by values that are defined in the CREATE TABLE statement.

V8 PartitioningV8 Partitioning

Index-Controlled <OR> Table-Controlled

DB2Catalog

DB2Catalog

Partitioning

Index

Partitioned

Table

PartitionedTable

V8 Partitioned FlexibilityV8 Partitioned Flexibility

Cluster Sequence Independence

Ind

ex C

on

trolle

d

Partitio

nin

g

Table ControlledPartitioning

Multiple Partitioned Indexes

Indexes Optional

Add Partitions

Alter Ranges

Future Enhancem

ents

Future Enhancem

entsFuture E

nhancements

Future Enhancem

ents

Rotate PartitionsRebalance Partitions

Partitioning Index Not Required

Enforce Limitkeys

Table Controlled Partitioning UsageTable Controlled Partitioning Usage

• Why?• Eliminate partitioning index

• Easier admin

• Enforces LIMITKEYs

• Logically cluster data

• Lower overhead

• Multiple partitionedindexes

• Partition independence

• Exploit new functions• CLUSTERING

• ADD PART

• ROTATE

• REBALANCE

• Future Enhancements

CREATE TABLESPACE tablespaceNUMPARTS 4(PARTITION 1 USING …PARTITION 2 USING …PARTITION 3 USING …PARTITION 4 USING …

) IN databaseCREATE TABLE table

(I_COLR,I_ACCN_PATN)PARTITION BY

(I_COLR ASC)(PARTITION 1 ENDING AT ‘BL’ …,PARTITION 2 ENDING AT ‘GR’ …,PARTITION 3 ENDING AT ‘RD’ …,PARTITION 4 ENDING AT ‘YL’ …)

CREATE TABLESPACE tablespaceNUMPARTS 4(PARTITION 1 USING …PARTITION 2 USING …PARTITION 3 USING …PARTITION 4 USING …

) IN databaseCREATE TABLE table

(I_COLR,I_ACCN_PATN)PARTITION BY

(I_COLR ASC)(PARTITION 1 ENDING AT ‘BL’ …,PARTITION 2 ENDING AT ‘GR’ …,PARTITION 3 ENDING AT ‘RD’ …,PARTITION 4 ENDING AT ‘YL’ …)

Creating Table Controlled PartitioningCreating Table Controlled Partitioning

Defines Data Buckets

Defined In The DB2 Catalog,Not By An Index!

Defines Elements &

Ranges, Not An Index!Defines Elements &

Ranges, Not An Index!

Converting to Table ControlledConverting to Table Controlled

ALTER INDEX clustering_index NOT CLUSTER;

(conversion to table-controlled partitioning)

COMMIT WORK;

Simple, Non Disruptive and Quick

ALTER INDEX clustering_index CLUSTER;(clustering index reestablished)

3

Other Ways to ConvertOther Ways to Convert

• Implicit ConversionINDEX CHANGES

ALTER INDEX partitioning-index NOT CLUSTER

CREATE INDEX … PARTITIONED

CREATE INDEX … ENDING AT … omitting CLUSTER keyword

TABLE CHANGES

ALTER TABLE … ADD PARTITION

ALTER TABLE … ROTATE PARTITION

ALTER TABLE … ALTER PARTITION n

Utility Changes

REORG REBALANCE

Listing Table Based PartitioningListing Table Based Partitioning

SELECT

CREATOR

,NAMEFROM SYSIBM.SYSTABLES

WHERE PARTKEYCOLNUM > 0

WITH UR

SELECT

CREATOR

,NAMEFROM SYSIBM.SYSTABLES

WHERE PARTKEYCOLNUM > 0

WITH UR

Table Based PartitioningTable Based Partitioning

Pitfalls

Can’t enforce uniqueness

without an index

Space map not as good as Universal TS in DB2 9

Power

Flexibility and Features

Just Do It!

Partitioned Index ConceptPartitioned Index Concept

Partitioned Index: An index that is physically partitioned. Both partitioning indexes and secondary indexes can be partitioned.

Partitioned IndexesPartitioned Indexes

Non-Partitioned Index

Partitioned Table

Partitioned Index

Ideal for Inter-Partition Queries!

Ideal for Intra-Partition Queries!

V8 Partition IndependenceV8 Partition Independence

BL GR RD YLYL

CREATE TABLE TAB(I_COLR CHAR(2),A_STAT CHAR(2),I_MONT CHAR(2))

PARTITION BY(I_COLR)



CREATE INDEX IXBON TAB(I_ACCN ASC)

PARTITIONED

CREATE INDEX IXBON TAB(I_ACCN ASC)

PARTITIONED

IXB Part 1 IXB Part 2 IXB Part 3 IXB Part 4

TAB Part 4TAB Part 3TAB Part 2TAB Part 1

2300

22111

2110

1445

1234

2301

2214

2112

1447

1235

2304

2217

2115

1448

1236

2307

2307

2219

2219

2119

2119

1449

1449

1238

1238

CREATE INDEX IXAON TAB(A_STAT ASC, I _COLR ASC)

PARTITIONED

CREATE INDEX IXAON TAB(A_STAT ASC, I _COLR ASC)

PARTITIONED

IXA Part 1 IXA Part 2 IXA Part 3 IXA Part 4WY

,BL

OH

,BL

GA

,BL

FL

,BL

AL

,BL

WY

,GR

WI,G

R

OH

,GR

GA

,GR

FL

,GR

WY

,RD

WI,R

D

GA

,RD

FL

,RD

AL

,RD

WY

,W

Y, Y

LY

L

PN

,P

N, Y

LY

L

GA

,G

A, Y

LY

L

FL

,F

L, Y

LY

L

AL

,A

L, Y

LY

L

REBUILDINDEX P1

LOAD

TS P2

REORG

TS P3

RECOVER

TS P4

4

Partitioned Index UsagePartitioned Index Usage

• Data Access Isolated by Partition

• Can make utilities more manageable

• If all indexes partitioned, have partition independence

• Excellent performance on intra-partition queries

Data Isolation

V8 Creating Indexes V8 Creating Indexes -- Minimal DisruptionMinimal DisruptionR

/O O

uta

ge

SELECT * FROM table WITH UR(non-peak time, prime the buffers)

-DIS DB(database) SPACENAM(tablespace) USE(check for any users)

CREATE INDEX index ON TABLE tableDEFER YES;

(new index established, index in RBDP)

REBUILD INDEX index STATISTICS(R/O outage - index is populated)

REBIND PACKAGE package(rebind plans/packages to use new index)

Create IndexCreate Index ImprovementsImprovements

• V8 REBUILD INDEX

• R/O Outage• Table

• Indexes

• DB2 9 REBUILD INDEX SHRLEVEL CHANGE

• Non-unique index R/W• Table & Indexes

• Unique index• INSERTs not allowed• DELETEs not allowed• UPDATEs not allowed that

affect unique index

Partitioned Index ListingPartitioned Index Listing

SELECTIXCREATOR

,IXNAMEFROM SYSIBM.SYSINDEXPART

WHERE

PARTITION = 1WITH UR

SELECTIXCREATOR

,IXNAMEFROM SYSIBM.SYSINDEXPART

WHERE

PARTITION = 1WITH UR

-DIS DB(db) SPACENAM(is)

NAME TYPE PART STATUSXRG97001 TS 0001 RW

-THRU 0004

-DIS DB(db) SPACENAM(is)

NAME TYPE PART STATUSXRG97001 TS 0001 RW

-THRU 0004

Partitioned IndexesPartitioned Indexes

Pitfalls

• Initial creation disruption

• Data access changes

• Cross partition queries

• Uniqueness enforcement

Power

• Utility independence

• Manageability

Clustering Index ConceptClustering Index Concept

clustering index An index that determines how rows are physically ordered (clustered) in a table space. If a clustering index on a partitioned table is not a partitioning index, the rows are ordered in cluster sequence within each data partition instead of spanning partitions.

5

Clustering Index ConceptClustering Index Concept

RD YL





CREATE INDEX IXBON TAB(I_MONT ASC)CLUSTER

CREATE INDEX IXBON TAB(I_MONT ASC)CLUSTER

TAB Part 4TAB Part 3TAB Part 2TAB Part 1

IXB

12

08

06

03

01

11

09

05

03

02

GRBL 12

10

07

04

03

12

09

05

04

01

12

12

12

11

11

10

09

09

08

07

06

05

05

04

04

03

03

03

02

01

01

SequenceSequence SequenceSequence SequenceSequence SequenceSequence

SequenceSequence

CL

US

TE

R

Any Index Can Be The Clustering Index!

The clustering index defines the physical sequence with each partition

Changing ClusteringChanging Clustering

ALTER INDEX old-clustering_index NOT CLUSTER;(clustering index removed)

COMMIT WORK;

ALTER INDEX new_clustering_index CLUSTER;(new clustering index established, table in AREO*)

REORG TABLESPACE tablespace

SHRLEVEL CHANGE STATISTICS COPYDDN(contents of each table put in new clustering sequence)

REBIND PACKAGE

Clustering Index UsageClustering Index Usage

• Improve sequential processing

• Improve clustered

• Improve cluster ratios

• Better access paths

• Optimizer behaves better

• Sequence matches processing

Clustering Index ListingClustering Index Listing

SELECT

CREATOR

,NAMEFROM SYSIBM.SYSINDEXES

WHERE

CLUSTERING = ‘Y’WITH UR

SELECT

CREATOR

,NAMEFROM SYSIBM.SYSINDEXES

WHERE

CLUSTERING = ‘Y’WITH UR

ClusteringClustering

PitfallsAccess path changes

PowerLogical clustering

Better sequential access

Rotate ConceptRotate Concept

Rotate: A movement of an active partition in a circular motion. Partition rotation reuses the oldest partition for new data.

6

ROTATE ConceptROTATE Concept

1Oldest

Limitkey A

2Old

Limitkey B

3New

Limitkey C

4Newer

Limitkey D

Delete Old Data New High

Part Limitkey

New High

Part Limitkey

ROTATE DDL Command1) Delete Oldest Partition Rows2) Reuse Oldest Partition

ROTATE DDL Command1) Delete Oldest Partition Rows2) Reuse Oldest Partition

1Oldest

Limitkey AA

Bit

Bucket

1Newest

Limitkey AAE

ROTATE DDL

ROTATE In ActionROTATE In Action

catg.DSNDB.db.ts.I0001.A0033




LP 4

LP 1

LP 2

LP 3

LP 4

LP 3

LP 2

LP 1

Logical PartitionSYSTABLEPART(V8)

Logical PartitionAfter The ROTATE

Physical PartitionDataset





Series of ROTATEsSeries of ROTATEs

P1

P2

P3

P4

P1

P2

P3

P4

P3

P4

P1

P2

P4

P1

P2

P3

P1

P2

P3

P4

1st Rotate 2nd Rotate 3rd Rotate 4th RotateALTER T

ABLE ROTATE ...

ENDING A

T (‘E’)

RESET;

ALTER TABLE R

OTATE ...

ENDING A

T (‘E’)

RESET;

Limitkey

‘A’

‘B’

‘C’

‘D’

‘E’

‘F’

‘G’

‘H’

ALTER TABLE R

OTATE ...

ENDING A

T (‘F’)

RESET;

ALTER TABLE R

OTATE ...

ENDING A

T (‘F’)

RESET;

ALTER TABLE R

OTATE ...

ENDING A

T (‘G’) R

ESET;

ALTER TABLE R

OTATE ...

ENDING A

T (‘G’) R

ESET;

ALTER TABLE R

OTATE ...

ENDING A

T (‘H’)

RESET;

ALTER TABLE R

OTATE ...

ENDING A

T (‘H’)

RESET;

Rotate Table UsageRotate Table Usage

Cyclic Tables with Fixed Cycles

DecDec

NovNov

SepSep

AugAug JunJun

MayMay

MarMar

FebFeb

OctOct AprApr

JulJul

JanJan

Rotating PartitionsRotating Partitions

ALTER TABLE tableROTATE PARTITION FIRST TO LASTENDING AT (limitkey) RESET;

Identifying Rotated TablesIdentifying Rotated Tables

SELECT DBNAME

,TSNAMEFROM SYSIBM.SYSTABLEPART

WHERE

DBNAME = ‘db' AND TSNAME = ‘ts'

AND LOGICAL_PART ^= PARTITION

WITH UR

SELECT DBNAME

,TSNAMEFROM SYSIBM.SYSTABLEPART

WHERE

DBNAME = ‘db' AND TSNAME = ‘ts'

AND LOGICAL_PART ^= PARTITION

WITH UR

SELECT

DBNAME

,TSNAMEFROM SYSIBM.SYSCOPY

WHERE

STYPE = ‘R’WITH UR

SELECT

DBNAME

,TSNAMEFROM SYSIBM.SYSCOPY

WHERE

STYPE = ‘R’WITH UR

-DIS DB(db) SPACENAM(ts)

NAME TYPE PART STATUS

SRG9700 TS 0002 RW -THRU 0004

SRG9700 TS 0001 RW

-DIS DB(db) SPACENAM(ts)


SRG9700 TS 0002 RW -THRU 0004

SRG9700 TS 0001 RW

?

7

ROTATE PowerROTATE Power

• Cyclic tables

• Managed by DB2

• Minimal disruptions Rotate PitfallsRotate Pitfalls

Wro

ng T

able

Wro

ng T

able

Non R

ecove

rable

Non R

ecove

rable

Double

Rota

te

Double

Rota

teLo

ng D

elet

es

Long

Del

etes

RE

OR

P S

tatu

s

RE

OR

P S

tatu

sE

nfo

rce L

imitkey

s

Enfo

rce L

imitkey

s

Addin

g Par

t

Addin

g Par

t

Logical Diff

erences

Logical Diff

erences

Phy

sica

l and

Phy

sica

l and

Rotate Sequence

Rotate Sequence

(~40 S

ec / m

illio

n)

(~40 S

ec / m

illio

n)

Universal Table Space ConceptUniversal Table Space Concept

Universal Table Space

A table space that is

both segmented and

partitioned.

The Power OfThe Power OfThe Power OfThe Power OfThe Power OfThe Power OfThe Power OfThe Power Of

Universal Table Space ConceptUniversal Table Space Concept

OneOneOneOneOneOneOneOne


Why Universal Table Space?Why Universal Table Space?

• Structure “Do Over”

• Time to fix

• Large only

• Single structure

• New enhancements

• Automation

• Older structures phased out

• We should move there

• DB2 x provides direction

• Solve chronic problems

• All tables are partitioned

• Better for you!

UTSUTS

2 Flavors of Universal Table Spaces2 Flavors of Universal Table Spaces

Partition ByGrowth

Partition ByRange

PBG PBR

8

DB2 9DB2 9

Universal Table Space UsageUniversal Table Space Usage

SegmentedSegmented

Tablespace Tablespace

SimpleSimple

Tablespace Tablespace UniversalUniversal


PartitionPartition

By GrowthBy Growth

PartitionedPartitioned

TablespaceTablespace

UniversalUniversal


PartitionPartition

By RangeBy Range

The FutureThe FutureV8V8

UTSUTS

Universal Table Space ImplementationUniversal Table Space Implementation

DB2 9

UDCL- Unload

- Drop

- Create- Load

DB2 9

UDCL- Unload

- Drop

- Create- Load

DB2 x

ALTER TABLESPACE SEGSIZE

& MAXPARTS

REORG TABLESPACE

SHRLEVEL CHANGE

DB2 x

ALTER TABLESPACE SEGSIZE

& MAXPARTS

REORG TABLESPACE

SHRLEVEL CHANGE

Listing Universal TablespacesListing Universal Tablespaces

SELECT

CREATOR

,NAMEFROM

SYSIBM.SYSTABLESPACEWHERE

TYPE in (‘G’

,’R’)WITH UR

SELECT

CREATOR

,NAMEFROM

SYSIBM.SYSTABLESPACEWHERE

TYPE in (‘G’

,’R’)WITH UR

Universal Table Space PowerUniversal Table Space Power

• Optimal Performance• APPEND

• Mass deletes

• Reordered Row Format

• TRUNCATE

• Large Tables

• INSERT

• ROTATE

• Space Maps

• Manageability

• Simplicity

• Growth

• Features

• Autonomic

Universal TablespaceUniversal Tablespace

PitfallsOne table per table spaceRestrictions on PBG (better than segmented)Can’t change Segsize or DssizeNot compatible with MEMBER CLUSTER (yet)DB2 9 & x - Unload Drop Create Load for PBRDB2 x - PBG converts with REORG

Clone Table ConceptClone Table Concept

Clone Table A table that is structurally identical to a base table. The base and clone table each have separate underlying VSAM data sets, which are identified by their data set instance numbers.

catg.DSNDBD.db.ts.I0001.A001catg.DSNDBD.db.ts.I000I00011.A001

catg.DSNDBD.db.ts.I0002.A001catg.DSNDBD.db.ts.I000I00022.A001

9

Clone Table UsageClone Table Usage

I0001

I0002

catg.DSNDBD.db.ts.I00011.A001


SYSTABLESPACE

2

1

BaseBase��

TablesTable Spaces

Base

Clone

Instance

Creating ClonesCreating Clones

catg.DSNDBD.db.ix.J0001.A001catg.DSNDBD.db.ix.J00011.A001

catg.DSNDBD.db.ix.I0001.A001catg.DSNDBD.db.ix.I00011.A001

catg.DSNDBD.db.ts.I0001.A001catg.DSNDBD.db.ts.I00011.A001P.BT

Bas

e O

bje

cts

catg.DSNDBD.db.ix.J0002.A001catg.DSNDBD.db.ix.J00022.A001

catg.DSNDBD.db.ix.I0002.A001catg.DSNDBD.db.ix.I00022.A001

catg.DSNDBD.db.ts.I0002.A001catg.DSNDBD.db.ts.I00022.A001P.CT

Clo

ne O

bje

cts

ALTER TABLE P.BT ADD CLONE P.CT;ALTER TABLE P.BT ADD CLONE P.CT;

Before Triggers

LOBS

XML

etc.

Before Triggers

LOBS

XML

etc.

What DoesnWhat Doesn’’t Get Cloned?t Get Cloned?

1. Data

2. Security

3. Run Statistics (shared)

4. Views & Aliases

5. Image Copies

Loading ClonesLoading Clones

catg.DSNDB.db.ix.J0002.A001catg.DSNDB.db.ix.J00022.A001

catg.DSNDB.db.ix.I0002.A001catg.DSNDB.db.ix.I00022.A001

catg.DSNDB.db.ts.I0002.A001catg.DSNDB.db.ts.I00022.A001P.CT

EXEC SQLINSERT INTO P.CT…..

END-EXEC

EXEC SQLINSERT INTO P.CT…..

END-EXECLOAD INTO TABLE P.CTLOAD INTO TABLE P.CT

SELECT * FROM P.NEWDATAINSERT INTO P.CT

SELECT * FROM P.NEWDATAINSERT INTO P.CT

Working on Clone Table w/UtilitiesWorking on Clone Table w/Utilities

• DB2 9 Utilities - CLONE Keyword• CHECK DATA / INDEX / LOB

• COPY / COPYTOCOPY / MERGECOPY

• DIAGNOSE / LISTDEF

• MODIFY RECOVERY

• QUIESCE

• BEBUILD / RECOVER

• REORG INDEX / TABLESPACE

• REPAIR

• UNLOAD (can specify table instead)

• DB2 9 Utilities – Without CLONE Keyword• DSN1Copy (ID with OBID/PSID)

• DSN1LOGP (clone PSID high order bit set to “1”)

• LOAD (works on table level)

• RUNSTATS (on base table only – doesn’t work on clone)

Exchanging ClonesExchanging Clones

I0001

I0002

SYSTABLESPACE

2

1

BaseBase��

Base

CloneInstance

I0001

I0002Base

CloneSYSTABLESPACE

2

1BaseBase��

Instance

EXCHANGE DATA BETWEEN P.BT AND P.CT;EXCHANGE DATA BETWEEN P.BT AND P.CT;

10

Dropping A Clone TableDropping A Clone Table

catg.DSNDB.db.ts.I0001.A001catg.DSNDB.db.ts.I00011.A001P.CT1





catg.DSNDB.db.ts.I0002.A001catg.DSNDB.db.ts.I00022.A001P.BT1

ALTER TABLE P.BT1 DROP CLONE;ALTER TABLE P.BT1 DROP CLONE;

Bit

Bucket

Clo

ne O

bje

cts

NAME TYPE

-------- ----

TS1 TSC1

TS1 TSB2

NAME TYPE

-------- ----

TS1 TSC1

TS1 TSB2



Clones In ActionClones In Action

Exchange

I0001

I0002

Create

Instance=1

Clone=

Exchange

Instance=2

Clone=Y

Exchange Drop

Instance=2Clone=Y

I0001 I0001

I0002 I0002 I0002

I0001 I0001

SYSTABLESPACE

SELECT *SELECT *

FROM TBFROM TBSELECT *SELECT *



FROM TBFROM TB

I0002

I0001

Instance=1

Clone=Y

Instance=1

Clone=YInstance=2

Clone=N

SELECT *SELECT *

FROM TBFROM TB

Listing Cloned TablesListing Cloned Tables

SELECT

DBNAME,TSNAME

,INSTANCEFROM

SYSIBM.SYSTABLESPACE

WHERE CLONE = ‘Y’

WITH UR

SELECT

DBNAME,TSNAME

,INSTANCEFROM

SYSIBM.SYSTABLESPACE

WHERE CLONE = ‘Y’

WITH UR

SELECTCREATOR

,NAMEFROM

SYSIBM.SYSTABLES

WHERE TYPE = ‘C’

WITH UR

SELECTCREATOR

,NAMEFROM

SYSIBM.SYSTABLES

WHERE TYPE = ‘C’

WITH UR

Cloned Table HistoryCloned Table History

SELECT

DBNAME

,TSNAME,DSNUM

FROM SYSIBM.SYSCOPY

WHERE ICTYPE = ‘C’

WITH UR

SELECT

DBNAME

,TSNAME,DSNUM

FROM SYSIBM.SYSCOPY

WHERE ICTYPE = ‘C’

WITH URSELECT

DBNAME,TSNAME

,DSNUM

FROM SYSIBM.SYSCOPYWHERE

ICTYPE = ‘A’

AND STYPE = ‘E’WITH UR

SELECT

DBNAME,TSNAME

,DSNUM

FROM SYSIBM.SYSCOPYWHERE

ICTYPE = ‘A’

AND STYPE = ‘E’WITH UR

-DIS DB(PRD) SPACE(TS*)


-------- ---- ----- -------

TS1 TS RW

TS2 TSB1 0001 RW

TS2 TSC2 0001 RW,ICOPY

TS3 TSB2 0001 RW,UT

TS3 TSC1 0001 RW

TS4 TSB2 0001 RW

TS5 TSB1 0001 RW

-DIS DB(PRD) SPACE(TS*)


-------- ---- ----- -------

TS1 TS RW

TS2 TSB1 0001 RW

TS2 TSC2 0001 RW,ICOPY

TS3 TSB2 0001 RW,UT

TS3 TSC1 0001 RW

TS4 TSB2 0001 RW

TS5 TSB1 0001 RW

Ta

ble

Insta

nc

eT

ab

le In

sta

nc

e

Cloned Table DisplayCloned Table Display

CloneCloneBaseBaseClonedCloned

PairPair

ClonedClonedPairPair

FormerFormerClonesClones

CloneCloneBaseBase

NeverNeverClonedCloned

i0001i0001

i0002i0002

i0002i0002

i0001i0001

Clone PowerClone Power

Ideal Way to Flip-Flop Data

No Invalid Packages, Plans, Cache

Minimal Outage on Exchange

Managed By DB2

11

Clone Table PitfallsClone Table Pitfalls

• Can’t Clone

• Non-UTS

• DB2 Catalog

• A Clone

• Temp Tables

• Materialized Query Tables

• With After Trigger

• With Referential Integrity

• Actively Versioned Table

• Base w/out defined datasets

• Base and Clone

• Separate Security

• Share ID column counter

• Share RUNSTATS

• Separate Object States

• Cloned Tables Can’t

• EXCHANGE by partition

• RENAME base table

• ALTER COLUMNS

• ALTER MAXPARTITIONS

• EXCHANGE w/out Claims

• FASTSWITCH

• Clone Dangers

• EXCHANGE & recoverability

• Double EXCHANGE

• Base / Clone Confusion

• DROP CLONE Deletes• Data

• Tablespaces & Indexes

• Other Stuff

HighLowSimpleNicheClone Tables

HighHighDifficult until

DB2 xWide


HighLowSimpleNicheRotate

Partitions

HighHighSimpleWideClustering

Index

HighModerateEasier in DB2

9Limited

Partitioned

Indexes

HighHighSimpleWide

Table

Controlled

Partitioning

Applic-

abilityConversion

EffortUsage

Probability

Pa

rtit

ion

ing

Fe

atu

res

UsageBenefit

The Power of PartitioningThe Power of Partitioning

DB2 Tablespaces Trends?DB2 Tablespaces Trends?

V1 V2 V3 V4 V5 V6 V7 V8 9 x X+1

Universal

pureXML

LOBS

Simple ?Index Ctrl Partitioned ?

Table Ctrl Partitioned ?

Segmented ?

Rules of ThumbRules of Thumb

• DB2 V8• Create only parts need

• Don’t specify extreme limitkey

• One table per tablespace

• Convert table controlled part

• Migrate from simple TS

• DB2 9• Create only parts need

• Don’t specify high limitkey

• One table per table space

• Create only universal TS

• Migrate to universal TS

• Migrate to pureXML

• DB2 x & Beyond• Migrate to universal TS

• Migrate to pureXML

The Promise of The Promise of ““NextNext””

• More online schema changes• Table space type

• Page size

• Utility Enhancements

• Performance• Quicker TRUNCATE

• Better Optimization

• Better Availability

• Maintainability

• Much more …..

DB2 DB2 DB2 DB2 xxxx

Changes that Require UDCLChanges that Require UDCL((UUnload / nload / DDrop / rop / CCreate / reate / LLoad)oad)

Reason DB2V7 DB2V8 DB2 9 DB2 x

Alter Partitioning Index X

Alter Clustering Index X

Add New Partitions X

REORG Rebalance Partitions X

Rotate Partitions X

DSSIZE=0 & Need >Max Parts X X X Reorg

Change DSSIZE X X X Reorg

Change Page Size X X X Reorg

Convert EBCDIC to Unicode X X X X

Change Column Datatype X X X X

Convert to UTS X Reorg

Reason DB2V7 DB2V8 DB2 9 DB2 x

Alter Partitioning Index X

Alter Clustering Index X

Add New Partitions X

REORG Rebalance Partitions X

Rotate Partitions X

DSSIZE=0 & Need >Max Parts X X X Reorg

Change DSSIZE X X X Reorg

Change Page Size X X X Reorg

Convert EBCDIC to Unicode X X X X

Change Column Datatype X X X X

Convert to UTS X Reorg

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Robert GoodmanRobert Goodman

[email protected]

Day: 1 Session: 2

Understanding the Power and Pitfalls of PartitioningUnderstanding the Power and Pitfalls of Partitioning

goodman understanding the power and pitfalls of ... the power and pitfalls...understanding the power...

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