1.4 - working with databases and database objects.odp

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© 2010 IBM Corporation

Information Management

Information Management Ecosystem PartnershipsIBM Canada Lab

Summer/Fall 2010

Working with Databases an Database

!b"e#ts in DB2$



2 © 2010 IBM Corporation

In%ormation Management

&gena

■ Servers, Instances, and Databases

■ Managing Instances

■ Creating a DB2 Database

■ Cataloging

■ Database (Data) Objects



( © 2010 IBM Corporation


Ser)ers* Instan#es* an Databases

■ ..uon installation, t!e DB2 Database Manager (rogram files) are coied to t!e server , and aninstance of t!e DB2 Database Manager is created.

■ ..instances are resonsible for managing s"stemresources and databases t!at fall under t!eir control.

■ ..databases are resonsible for managing t!estorage, modification, and retrieval of data.

■ I#S$%#C& is a logical database serverenvironment.

DB2 vie's t!e 'orld as a !ierarc!" of objects

Database1

Database2

Instan#e

Ser)er



+ © 2010 IBM Corporation

In%ormation ManagementI

B M D B 2 ,

M o r e o n i n s t a n c e s

- h e e % a u l t i n s t a n # e % o r a p a r t i # u l a r s . s t e m i s e % i n e b . t h e

D B 2 I # S $ % # C & e n v i r o n m e n t v a r i a b l e I n i t i a l l . % o r W i n o w s

e % a u l t i s 0 D B 2 a n % o r i n u 3 / 4 n i 3 i t i s 0 b 2 i n s t 1

D B 2 , I n s t a n # e M a n a g e m e n t C o m m a n s 5

u r o s eC o m m a n d

S t o p s t h e D B 2 D a t a b a s e M a n a g e r b a # k g r o u n

p r o # e s s e s % o r t h e # u r r e n t i n s t a n # e

b 2 s t o p

S t a r t s t h e D B 2 D a t a b a s e M a n a g e r b a # k g r o u n

p r o # e s s e s % o r t h e # u r r e n t i n s t a n # e

b 2 s t a r t

i s t s a l l i n s t a n # e s t h a t h a ) e b e e n e % i n e b 2 i l i s t

D e l e t e s 6 r o p s 7 a n e 3 i s t i n g i n s t a n # e b 2 i r o p 8 I n s t a n c e N a m e 9

C r e a t e s a n e w i n s t a n # e b 2 i # r t 8 I n s t a n c e N a m e 9



: © 2010 IBM Corporation


Instan#es

■ Stand*alone DB2 environment

■ Can !ave multile instances er dataserver

■ %ll instances s!are t!e same e+ecutablebinar" files

■

&ac! instance !as its o'n configuration■ Different soft'are level for an instance

Command Descrition &+amle

db2start Start t!e default instancedb2start

db2sto Sto t!e current instance db2stop -f

db2icrt Create an instance db2icrt –u db2fenc1 db2inst1

db2idro Dro an instance db2idrop –f db2inst1

db2ilist ist all instances db2ilist

db2imigr Migrate an instance after ugrading DB2 db2imigr –u db2fenc1 db2inst1

db2iudt -date an instance after installation of a fi+ ac db2iupdt –u db2fenc1 db2inst1


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DB an DBM #on%igurations

Descrition &+amle

/ie' Database Manager Settings db2 get dbm cfg show detail

C!ange a Database Manager Setting db2 update dbm cfg using <parameter> <value>

Descrition &+amle

/ie' Database Settings db2 get db cfg for <database>

db2 connect to <database>

db2 get db cfg show detail

C!ange a DB Setting db2 update db cfg using logprimary 10

UP!"# $ %&' U()*' +,'#"!)* #%,.#/ U(##)" ,*

%!++ (/(P,%'#"$%,*&)'34

(#+#%" $%,*&)'"/P#5 +,'#"!)*5 U(##)" &,6 (#((),*$%,*&)'

<etrie)ing original )alue 6on isk7an upate )alue 6in memor.7

=uer.ing the resulting global

-emporar. table 6DB>C!?FI@7

Change )alue o% logretain Ausere+it b #on%ig parameters

<esult5


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Database Storage Moel


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DB2 Storage Model

■ O0IC% S$O1%0& MOD& -&BS are mae up o% C!4M?S an <!WS -&BS are pla#e into table spa#es -&B SE&C #an ha)e more then one table

● 3SIC% S$O1%0& MOD&● C!?-&I?< is a ph.si#al storage e)i#e● Can be a e)i#e * ire#tor. or a %ile● Container is assigne to table spa#e✔


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-&B SE&CS

■ $%B& S%C&S is a logical sace bet'een data and storage

devices. Consists o% more then one #ontainers -ables* regular ata* ine3es* an long ata resies in table

spa#es

●

S45 C1&%$& 6 %$&1 6 D1O $%B&S%C&S● $o disla" tablesaces info5

● IS- -&BSE&CS 8 S!W D-&I9●

●

Details about containers can be obtained 'it! a follo'ingcommand.● IS- -&BSE&C C!?-&I?<S %or tablespa#e>i

8S!W D-&I9

●





DB2 Storage55 -able Spa#es !)er)iew

■ ogical objects in bet'een logical

table and !"sical containers

■ %llo's assignment of t!e locationof data to articular logical devicesor ortions t!ereof

■ %ll tables, inde+es, and ot!er dataare stored in a table sace

■ Can be associated to a secificbuffer ool Containers can be files,

directories or ra' devices





$%B&S%C& S$O1%0& M%#%0&M&#$

■ S"stem 7 Managed Sace (SMS)5

!SGs FI SHS-M M&?&@< allo#ates an manages thespa#e

● Database Managed Sace (DMS)5●

ere* the Database manager #ontrols the storage spa#e●

● %utomatic Storage 'it! DMS5● Databases are enable %or automati# storage ha)e a set o%

one or more storage paths asso#iate with them● & table spa#e #an be e%ine as manage b. automati#

storageJ an its #ontainers assigne an allo#ate b. DB2base on those storage paths

● Hou #annot enable/isable storage on#e it has been e%ine%or atabase

● De%ault t.pe in DB2 ,



1' © 2010 IBM Corporation


DB2 Storage55 -able Spa#e Management

■ S"stem Managed Saces (SMS) Data store in %iles representing ata ob"e#ts Spa#e is allo#ate on eman

&##ess to ata #ontrolle using stanar I/! %un#tions o% the !SIeal %or small* personal atabases an atabases that grow/shrink rapil.

● ow maintenan#e an monitoring

■ Database Managed Saces (DMS) Data store in %iles or on raw e)i#es

Storage spa#e preKallo#ate in %ile s.stem* t.pi#all. #ontiguousph.si#all.Ieal %or per%orman#eKsensiti)e appli#ations

● In#rease maintenan#e an monitoring

%#!"# "!$+#(P!%# tbsp1 6!*!'# $/ (/("#6U()*' 37d89acctbsp75 7e89acctbsp75 7f89acctbsp74

%#!"# "!$+#(P!%# tbsp2P!'#():# ; 6!*!'# $/ !"!$!(#

U()*' 3&)+# 7 =storage=dms17 10 64 !U",#():# /#(



1( © 2010 IBM Corporation


DB2 Storage55 -able Spa#e Management

■ %utomatic Storage $able Sace

DBM #reates an e3tens #ontainers as neee up thelimits impose b. the storage paths asso#iate with theatabase

&utomati#all. hanles resiLing table spa#es Creates a DMS table spa#e %or regular/large table spa#es

Creates a SMS table spa#e %or user or s.stem temporar.table spa#es

%#!"# !"!$!(# mydb !U",6!")% (",!'# /#(

%,**#%" ", mydb

%#!"# "!$+#(P!%# tbsp1 6!*!'# $/ !U",6!")% (",!'#

#e' DB 8 $BSare !andled b" automatic storage

b" D&9%-$



1+ © 2010 IBM Corporation


DB2 Storage55 Bu%%er Eools

■ %rea of main memor" used to cac!e table

and inde+ data■ &ac! database must !ave at least one

buffer ool B. e%ault IBMDF&4-BE is use

Bu%%er pools #an be #reate* roppe or altere

SHSC&-B4FF<E!!S #atalog )iew

a##esses the in%ormation %or the bu%%er poolse%ine in the atabase

■ &ver" table sace associates a secificbuffer ool of t!e same age si:e

Mat#h bu%%er pool siLe with purpose o% tableto in#rease hit ratio

■ Self*$uning Memor" Manager (S$MM)available

%#!"# $U&&#P,,+ bp? P!'#():# %#!"# "!$+#(P!%# tbsp1 P!'#():# $U&&#P,,+ bp?



1: © 2010 IBM Corporation


Databases

■ ;!at maes u a DB2 database<

& DB2 atabase is mae up o% a #olle#tion o% ob"e#ts

& atabase #ontains the %ollowing ob"e#ts5

-ables* )iews* ine3es* s#hemas

o#ks* triggers* store pro#eures* pa#kages

Bu%%er pools* log %iles* table spa#es

■ ;!ic! tools can !el "ou create DB2 databases<

First Steps

Control Center 6@4I wiLar7

Comman ine Ero#essor 6CE7



1; © 2010 IBM Corporation


Creating a DB2 Database First Steps

■ %s art of t!e DB2installation rocess, t!e9irst Stes anel isdisla"ed allo'ing t!euser to generate a

number of a samledatabases to 'or 'it!

■ $o launc! t!e first stesinterface issue db2fs

from a DB2 commandline





-.pi#al Dire#tor. ierar#h. -ree

DATABASE_PAT

INSTANCE_NAME

N!DE""""

DATABASE_NAME

-0000000

-0000001

C0000000-ME

-0000002

S=00003

DB2N?-

S=!@DI<

o#ation spe#i%ie when the atabase was #reate !< the)alue o% the dftdbat! DBM #on%iguration parameter

Dire#tories #ontaining %ile or subKire#tor.#ontainers %or the S3SC%$S%C&* $&MS%C&=*an -S&1S%C&= table spa#es

Dire#tor. with the name o% the instan#e that #ontrols the atabase

Dire#tor. with the name o% the noe number assigne to thispartition 6alwa.s #OD&>>>> i% atabase is nonpartitione7

Dire#tor. with the name that was assigne to theatabase

Database ire#tor. 6name mat#hes the atabasetoken assigne to the atabase7

Dire#tor. %or e)ent monitor ata

Dire#tor. %or transa#tion log %iles

Files neee %or atabase re#o)er. anbookkeeping tasks*



1, © 2010 IBM Corporation


Creating a DB2 Database Comman ine

■ $!e C1&%$& D%$%B%S& command initiali:es a ne' database

>>-%#!"#--@-!"!$!(#-@--database-name----------------------->

CREATE DATABASE TESTDB1

CREATE DATABASE TESTDB2 ON C:

CREATE DATABASE TESTDB3

AUTOMATIC STORAGE YESON C:,D: DBPATH ON E:

atabaseKname

Database is#reate on ri)e C5

&utomati# store is enable anstorage paths are C5 an D5

Database is#reate on ri)e 5

3amples5





;it! Database, DB2 automaticall" creates■ $!e t!ree table saces are created5

S3SC%$S%C&5 -his is where DB2 s.stem #atalog is kept

that tra#ks all o% the metadata asso#iate with DB2 ob"e#ts $&MS%C&=* & temporar. work area where DB2 #an

pla#e intermediate results -S&1S%C&=K a pla#e where all user ob"e#ts 6tables*

ine3es7 resies b. default

● Con%iguration in%ormation 6DB CF@7

● og %iles* istor. %iles et#





With atabases* DB2 automati#all. #reates

Catalog table sacesS3SC%$S%C&

(= re?uired)

● Catalog tables 'it! metadata

● Must e+ist

ConfigurationInformation (DB C90)● og 9iles

● istor" 9iles

● &tc.

-ser $able Saces

-S&1S%C&=

(= or more re?uired)

● Default user table sace

● Can be deleted

● %ll user defined tables

S"stem temorar"table sace

$&MS%C&=

(= re?uired)

● S"stem temorar" sace

● ;or area for oerations,

for e+amle5 join, sorts





DB2 Data Ser)er Clients

IBM Data Server Drivers

ight weight eplo.ment solution %or ISNs

Must be installe manuall.

● IBM Data Server Driver for @DBC and S4@ Oa)a store pro#eures an userK

e%ine %un#tions

ODBC* S=O

● IBM Data Server Driver for ODBC and CI !DBC &EI* or CI &EI

● IBM Data Server Driver acage

!DBC* CI* ?-* ! DB* EE*<ub.* ODBC* or S=O

IBM Data Server 1untime Client

ODBC* &D!?-* ! DB* !DBC* CI* EE* an<ub.

as CE but @4I tools are not in#lue

Support D&E e3ploitation* -CE/IE an ?ameEipe* #ataloging

IBM Data Server Client

&ll the %un#tionalit. o% IBM Data Ser)er <untimeClient

Elus %un#tionalit. %or atabase aministration*appli#ation e)elopment* an #lient/ser)er#on%iguration

Capabilities in#lue @4I tools su#h as#on%iguration assistant* #ontrol #enter* )isualstuio tools



2' © 2010 IBM Corporation


Cataloging

■ DB2 !as multile directories t!at are used to access

databases

-he s.stem atabase ire#tor. #ontains a list anpointer to where all the known atabases #an be %oun(list db director")

-he noe ire#tor. #ontains in%ormation relating to howan where remote s.stems or instan#es #an be %oun( list node director")

-he Database Conne#tion Ser)i#es 6DCS7 Dire#tor. #ontains in%ormation relating to how an whereatabases on D<D& s.stems #an be %oun( list dcs director")



2( © 2010 IBM Corporation


Wa.s o% Cataloging a Database at a Client

■ %utomated configuration using discover"

Searc! discover" #lient sear#hes ser)er on the network

Ano'n discover" one parti#ular ser)er is Puerie %orin%ormation

■ %utomated configuration using access rofiles

Server rofiles #ontains in%ormation on instan#es anatabases

Client rofiles use to upli#ate in%ormation %rom one #lient toanother

■ Manual configuration Con%iguration &ssistant 6graphi#al7

Data Stuio 6graphi#al7




2+ © 2010 IBM Corporation


Cataloguing55 Setting 4p Communi#ations

■ $o use a remote database5

1 Catalog the remote s.stem 6noe72 Catalog the atabase within the remote noe

■ tools available5 Con%iguration &ssistant 6graphi#al7 Data Stuio 6graphi#al7


authenti#ation>t.pe

catalog database sample as mysample at node db2node authentication server

atabase>aliasatabase>name noe>name

catalog tcpip node db2node remote mysystem serverdb2tcp2

alias host>name or ip>ar

ser)i#e>nameor port>number

db2 list AdatabaseBnodeCdirectory

#an be use to %in the locall"catalogued DB or noe



2: © 2010 IBM Corporation


Database 6Data7 !b"e#ts

■ Database objects, also no'n as data objects, are used to

control !o' all user data (and some s"stem data) is storedand organi:ed 'it!in a DB2 database

-ser*Defined9unctions

Storedrocedures

acages

$riggersSe?uences%liasesInde+es

/ie's$ablesSc!emas



2; © 2010 IBM Corporation


Database Object 5 SC&M%





S#hemas

■ Sc!emas (uni?ue identifiers) are objects t!at are used to

logicall" classif" and grou ot!er objects in t!e database.

■ Sc!emas !ave rivileges associated 'it! t!em t!at allo' t!esc!ema o'ner to control '!ic! users can create, alter, anddro objects 'it!in t!em.

■ Benefits of a sc!ema5

-eious to sear#h through entire atabase %or ob"e#ts with thesame name

-he name o% ea#h ob"e#t nees to be uniPue onl. within its s#hema

&##ess #ontrol

When an ob"e#t is #reate without spe#i%.ing a s#hema* ob"e#t willbe asso#iate with an impli#it s#hema using the authorization ID



2, © 2010 IBM Corporation


S#hemas

■ Most database objects !ave a t'o*art object name

-he first part being the s#hema name 6or Puali%ier7

-he second is the ob"e#t name

■ ;!en an object is created, "ou can assign it to a secific sc!ema

SCHEMA_NAME.OBJECT_NAME

■ 9or e+amle

CREATE SCHEMA P!/,++

CREATE TABLE P!/,++("!&&

-able name S-&FF isassigne to the E&H<! s#hema



'0 © 2010 IBM Corporation


S#hemas 3ample 55 4sing the #omman line

■ %#!"# (%D#6! payroll !U"D,):!"),* user1E

■ %,66#*" ,* (%D#6! payroll )( 7schema for payrollapplication7E

Creates a s#hema %or anini)iual user with the

authoriLation ID Q4S<1Q

S#hemaname

S#hema to#omment on

Commentstring





-ables

■ % relational database resents data as a collection of tables

■ % table consists of data logicall" arranged in columns andro's (records)

ea#h #olumn #ontains )alues o% the same ata t.pe

ea#h row #ontains a set o% )alues %or ea#h #olumn a)ailable

■ $!e storage reresentationof a ro' is called a record

■ t!e storage reresentationof a column is called a field

■ eac! intersection of a ro'and column is called a value

D&$ID D&$#%M& COS$C&#$&1

A000 &DMI?IS-<&-I!? 102+0

B001 E&??I?@ 1020

C001 &CC!4?-I?@ 20(+0

D001 4M&? <S!4<CS '0200

E001 < A D +0120

E002 M&?4@&C-4<I?@ +0220

E003 !E<&-I!?S +02'0

<e#or6<ow7

DE&<-M?- -able

Fiel6Column7

Nalue





-ables ' Main -.pes o% -ables

■ Base $ables

4serRe%ine tables esigne to hol persistent user ata

CREATE TABLE dep!"#e$"

%dep"&d CHAR%'(,

dep"$#e )ARCHAR%30(,

*+"*e$"e! INTEGER(-

■ 1esult $ables DB2 Database ManagerRe%ine tables populate with rows retrie)e

%rom one or more base tables in response to a Puer.

■ Declared $emorar" $ables

4serRe%ine tables use to hol nonpersistent ata temporaril.* on behal%o% a single appli#ation

3pli#itl. #reate b. an appli#ation when the. are neee an impli#itl.estro.e when the appli#ation that #reate them terminates its lastatabase #onne#tion

Create with #%+!# '+,$!+ "#6P,!/ "!$+# statement

tableKname#olumnKname5

names a #olumn o%the table ataKt.pe



'' © 2010 IBM Corporation


Niews

■ /ie's can be seen as virtual tables derived from one or more

tables or vie's Create to limit a##ess to sensiti)e ata or group together ata

%rom i%%erent tables in a single ob"e#t

Niews o not #ontain real ata

!nl. the )iew e%inition itsel% is a#tuall. store in the atabase

Can be eletable* upatable* insertable* an reaKonl.

When #hanges are mae to ata through a )iew* the ata is#hange in unerl.ing table itsel%

Can be use inter#hangeabl. with tables when retrie)ing ata

● C#EATE $IE% dept_&ie' AS SELECT ( )#!M department



'( © 2010 IBM Corporation


Niews 3ample 55 Simple )iew re%eren#ing two base tables

&MID #%M& I#S$ID

001 O&@@<* MIC H01

002 <IC&<DS* I- G01

003 W!!D* <!??I G01

00' W&--S* C&<I D01

00 WHM&?* BI B01

00/ O!?S* B<I&? G01

I#S$ID #%M&

H01 &<M!?IC&

G01 @4I-&<

D01 D<4MS

B01 B&SS @4I-&<

01 HB!&<D

S01 S&T&E!?

&MID #%M& I#S$#%M&

001 O&@@<* MIC HARMONICA

002 <IC&<DS* I- GUITAR

003 W!!D* <!??I GUITAR

00' W&--S* C&<I DRUMS

00 WHM&?* BI BASS GUITAR

00/ O!?S* B<I&? GUITAR

CREATE )IE myview%e#p&d, $#e, &$"$#e( AS

SELECT T1.e#p&d, T1.$#e, T2.$#eROM T1, T2

HERE T1.&$"&dT2.&$"&d

)iewKname #olumnKname6s7

Ienti%ies the )iewe%inition

De%ines the)iew

-1 -2

m"vie'



'+ © 2010 IBM Corporation


Ine3es

■ %n inde+ is an object t!at contains an ordered set of ointers

t!at refer to ro's in a base table. $!e" are based uon oneor more columns but stored as a searate entit".

D&$ID 1O;

A000 +

B001 2

C001

D001 11

E001 '

E002 :

E003 (F001 1

F002 ,

F00' ;

@010 10

DE&<-M?- -able

D&$ID D&$#%M& COS$C&#$&1

001 &DMI?IS-<&-I!? 102+0

B001 E&??I?@ 1020

E001 &CC!4?-I?@ 20(+0

E003 4M&? <S!4<CS '0200

A000 < A D +0120

E002 M&?4@&C-4<I?@ +0220

003 !E<&-I!?S +02'0

C001 M&<-I?@ (2100

F002 S&S (2200@010 C4S-!M< S4EE!<- (2'00

D001 @& :0:0

DE-ID Ine3 <ow 1

<ow 2<ow '

<ow (

<ow +

<ow :

<ow ;

<ow

<ow ,<ow 10

<ow 11



': © 2010 IBM Corporation


Ine3es Importan#e

■ ..rovide a fast, efficient met!od for locating secific ro's of

data in ver" large tables.

■ ..rovide a logical ordering of t!e ro's of a table

● ..can be used to enforce t!e uni?ueness of records stored ina table.

■ ..can force a table to use clustering storage, '!ic! causest!e ro's of a table to be !"sicall" arranged according to t!eordering of t!eir inde+ column values.

■

C1&%$& -#I4-& I#D& emnoind+ O#emlo"ees(emno)



'; © 2010 IBM Corporation


Ine3es 3ample

■ Suose "ou !ad t!e follo'ing &MO3&&S base table..

..and "ou 'anted to create an inde+ suc! t!at t!e inde+ e"

consists of t!e column named &M#O and all emlo"ee numbersentered 'ill be guaranteed to be uni?ue..

Column#ame ...

Data $"e ...

EMPNO I?-@<

NAME C&<6207

LNAME C&<6'07

TITLE C&<6107DEPARTMENT C&<6207

SALARY DCIM&6:*27



' © 2010 IBM Corporation


Ine3es 3ample 6#ontinue7

CREATE U*)FU# INDE4 e#p$+_&$d5ON e#p6+7ee%e#p$+(

U*)FU# pre)ents the table %rom

#ontaining two or more rows with thesame )alue o% the ine3 ke.

tableKname ienti%ies a table onwhi#h an ine3 is to be #reate

#olumnKname ienti%ies a #olumnthat is to be part o% the ine3 ke.



', © 2010 IBM Corporation


3ample o% I?DT

■ C<&- -&B arts 6 part>no I?- 6,7 ?!- ?4*

part>name N&<C&<62(7* pert>remain I?- 6,77

■

Creating an I?DT on #olumn part>no

C1&%$& -#I4-& I#D& id+artno O# arts(artno)



(0 © 2010 IBM Corporation


&liases

■ %n alias is an alternate name for an object suc! as a table or

vie'.

■ ike other ob"e#ts* an alias #an be #reate* roppe* an ha)e#omments asso#iate with it

■ &liases are publi#l. re%eren#e names* so no spe#ial authorit. orpri)ilege is rePuire to use them

owe)er* a##ess to the table or )iew that an alias re%ers to stillrePuires appropriate authoriLation

■ &liases #an be #reate b. e3e#uting the %#!"# !+)!( S=

statement





&liases

■ &+amle

.ou wante to #reate an alias that re%eren#es a table nameME!HS an .ou wante to assign it the name MEI?F!

%#!"# !+)!( e#p&$8+ &, e#p6+7ee

■ ;!" use an alias instead of t!e actual object name<

So that S= statements #an be #onstru#te su#h that the. areinepenent o% the Puali%ie names that ienti%. the base tables or)iews the. re%eren#e

?ames the alias -he name must notienti%. a table* )iew* ni#kname* or alias

that e3ists in the #urrent atabase

Ienti%ies the table*)iew* ni#kname* or

alias %or whi#h aliasK

name is e%ine





S&4-&#C&

■ Se?uence is an ob"e#t that use to generate ata )alues

automati#all.■ De%ault in#rement )alue is 1

■ E<NI!4S N&4 e3pression returns the most re#ent generategenerate )alue %or sePuen#e

■ ?T- N&4 e3pression returns the ne3t sePuen#e )alue

■ MA*$AL+E of a se,-ence can be e,-a. to MIN$AL+E/

■

■

CREATE SE!E"CE em#$id START %IT& '(( I"CREME"T B) '(CAC&E *



(' © 2010 IBM Corporation


SePuen#es

■ % se?uence is an object t!at is used to generate data values

automaticall". -nlie an identit" column, a se?uence is nottied to an" secific column or an" secific table.

&n ientit. #olumn pro)ies a wa. %or DB2 to automati#all.generate a uniPue numeri# )alue %or ea#h row that is ae to thetable

■ Se?uences !ave t!e follo'ing c!aracteristics5

Nalues generate #an be an. e3a#t numeri# ata t.pe that has as#ale o% Lero 6SM&I?-* BI@I?-* I?-@<* or DCIM&7

Conse#uti)e )alues #an i%%er b. an. spe#i%ie in#rement )alue

Counter )alues are re#o)erable Counter )alues are re#onstru#te%rom logs when re#o)er. is rePuire

Nalues generate #an be #a#he to impro)e per%orman#e



(( © 2010 IBM Corporation


SePuen#es

■ Se?uences can generate values in one of t!ree 'a"s5

B. in#rementing or e#rementing b. a spe#i%ie amount* withoutbouns

B. in#rementing or e#rementing b. a spe#i%ie amount to auserRe%ine limit an stopping

B. in#rementing or e#rementing b. a spe#i%ie amount to a

userRe%ine limit* an then #.#ling ba#k to the beginning anstarting again

■ &+amle5 if "ou 'anted to create a se?uence t!at generatesnumbers, starting 'it! t!e number =>> and incrementing

eac! subse?uent number roduced b" =>■ %#!"# (#FU#*%# e#p_&d ("!" G)"D 100 )*%#6#*" $/ 10

?ames the sePuen#e

Spe#i%ies the %irst

)alue %or the sePuen#e

Spe#i%ies the inter)albetween #onse#uti)e

)alues o% the sePuen#e



(+ © 2010 IBM Corporation


&+amle of S&4-&#C&

C<&- S=4?C m.>seP S-&<- WI- + I?C<M?- BH + C&C +

● 4ser1 su##ess%ull. e3e#utes the %ollowing statements in Conne#tion15

/%-&S #&$ /%-& 9O1 m"se? I#$O 5con=!var

/%-&S #&$ /%-& 9O1 m"se? I#$O 5con=!var

4ser2 su##ess%ull. e3e#utes the %ollowing statement in Conne#tion25

/%-&S #&$ /%-& 9O1 m"se? I#$O 5con2!var

● &%ter 4ser1 A 4ser2 are %inishe* 4ser' e3e#utes the %ollowing statement in

Conne#tion'5

S&&C$ #&$ /%-& 9O1 m"se? 91OM s"sibm.s"sdumm"=

What will be output i% abo)e Puer. is e3e#ute5

Ans+er, **



(: © 2010 IBM Corporation


&+amle of S&4-&#C&

C1&%$& S&4-&#C& m"se?uence C%C& => O1D&1

■ $!e follo'ing statements are successfull" e+ecuted in se?uencet!roug! searate database connections5

■

CO##&C$IO#= * /%-&S #&$ /%-& 9O1 m"se?uence I#$O 5con=!var

CO##&C$IO#2 * /%-&S #&$ /%-& 9O1 m"se?uence I#$O 5con2!var

CO##&C$IO#= * /%-&S #&$ /%-& 9O1 m"se?uence I#$O 5con=!var

■

■ 4uestion 5 ;!at is t!e current value of t!e 5con=!var !ost

variable<■ %#S;&15

■



(; © 2010 IBM Corporation


SePuen#e 3ample

Consider t!e follo'ing scenario. ;e !ave a table, table=, '!ic! !as onl" one columnstoring an integer value. $!e follo'ing statements are e+ecuted successfull" in t!e orderss!o'n5

C1&%$& S&4-&#C& m"se? S$%1$ ;I$ = I#C1&M&#$ B3 = C%C& E

I#S&1$ I#$O table= /%-&S (#&$ /%-& 9O1 m"se?)F


%fter a db2 terminate and reconnection to t!e database, t!e follo'ing statement 'asissued5


S&&C$ G 91OM table=

;!at value 'ill be t!e last value returned b" t!e ?uer"<

%ns5 H

I % ti M t



( © 2010 IBM Corporation


-riggers

■ % trigger defines a set of actions t!at are erformed in

resonse to an insert, udate, or delete oeration on asecified table.

■ ike #onstraints* triggers are o%ten use to en%or#e ata integrit.an business rules

■ 4nlike #onstraints* triggers #an also be use to upate othertables* automati#all. generate or trans%orm )alues %or inserte orupate rows* an in)oke %un#tions to per%orm tasks su#h asissuing errors or alerts

■ 4sing triggers pla#es the logi# that en%or#es business rules insiethe atabase

■ &+. C1&%$& $1I00&1 a"raise B&9O1& -D%$& O#emlo"ees 9O1 &%C 1O;S&$ ne'.salar" salar" G =.=

I % ti M t



(, © 2010 IBM Corporation


&+amle of $1I00&1

C1&%$& $%B& tab= (col= I#$)F

C1&%$& $%B& tab2 (col= I#$)F

C1&%$& $1I00&1 trig= %9$&1 -D%$& O# tab=

1&9&1&#CI#0 #&; %S ne'=

9O1 &%C 1O; MOD& DB2S4

I#S&1$ I#$O tab2 /%-&S(ne'=.col=)F

■

■ I#S&1$ I#$O tab= /%-&S(2),()F

■

;!at 'ill be t!e outut 5

■ S&&C$ count(G) 91OM tab2

Outut5>

■

I % ti M t



+0 © 2010 IBM Corporation


-riggers 3ample

■ Suose "ou !ad t!e follo'ing &MO3&&S base table..

..and "ou 'anted to create a trigger for &MO3&&S t!at 'illcause t!e value for t!e column named &M#O to be incrementedeac! time a ro' is added to t!e table

Column #ame ... Data $"e ...

EMPNO I?-@<

NAME C&<6207

LNAME C&<6'07

TITLE C&<6107

DEPARTMENT C&<6207

SALARY DCIM&6:*27






-riggers 3ample #ontG

%#!"# ")''# e#p$+_&$*

!&"# )*(#" ,* e#p6+7ee&, #!%D ,G UP!"# e#p$+ (#" e#p$+ e#p$+ 9 1

?ames thetrigger

Spe#i%ies the a#tion to be per%ormewhen a trigger is a#ti)ate

-he a#tion is to be

applie on#e for each ro' a%%e#te b. the trigger

-he a#tion is to be applie after the #hanges #ause b. the

a#tual upate o% the sub"e#t table






4serKe%ine Fun#tions

■ -serJdefined functions (-D9s) are secial objects t!at are

used to e+tend and en!ance t!e suort rovided b" t!ebuiltJin functions available 'it! DB2.

■ 4nlike DB2Gs builtRin %un#tions* userRe%ine %un#tions #an takea)antage o% s.stem #alls an DB2Gs aministrati)e &EIs

■ 4serKe%ine %un#tions are #reate 6or registere7 b. e3e#utingthe %#!"# &U*%"),* S= statement

■ S= S#alar* -able* or <ow Constru#te using onl. S=statements an #an return a )alue* row or table

■ 3ternal S#alar/-able Written using a highKle)el programminglanguage su#h as C* CUU* or Oa)a an returns a single )alue ortable




+' © 2010 IBM Corporation


Store Ero#eures

■ %n S4 stored rocedure is an ordinar" rogram comosed

entirel" of S4 statements t!at can be called b" analication.

■ Store pro#eures #an be #alle lo#all. or remotel.

■ &n e3ternal store pro#eure is a store pro#eure that is written

using a highKle)el programming language

3ternal store pro#eures #an be more power%ul than S= storepro#eures be#ause the. #an take a)antage o% s.stem #alls anaministrati)e &EIs along with S= statements




+( © 2010 IBM Corporation


Store Ero#eures &)antages / Bene%its

■ 1educes net'or traffic

■ %ccess to features t!at e+ist onl" on t!e server

■ &nforcement of business rules

■ % remote stored rocedure rovides t!e most advantages5

It splits the appli#ation logi# an en#ourages an e)en istributiono% the #omputational workloa

It pro)ies an eas. wa. to #all a remote program

In%ormation ManagementI

B M D B 2 ,



++ © 2010 IBM Corporation


C a l l i n g a S t o r e d r o c e d u r e

C < & - E < ! C D 4 < g e t > s a l e s

6 I ? P u o t a I ? - @ < * ! 4 - r e t # o e C & < 6 + 7 7D H ? & M I C < S 4 - S - S 1 & ? @ 4 & @ S =

B @ I ?

D C & < s P l s t a t e C & < 6 + 7 V

D C & < s a l e s > r e s u l t s C 4 < S ! < W I - < - 4 < ? F ! <S & & C $ s a l e s e r s o n , S - M ( s a l e s ) % S t o t a l s a l e s9 1 O M s a l e s 0 1 O - B 3 s a l e s e r s o n

% / I # 0 S - M ( s a l e s ) K ? u o t a FD C & < T I - & ? D < F ! < S = T C E - I ! ?

S - r e t # o e s P l s t a t e V ! E ? s a l e s > r e s u l t s VS - r e t # o e s P l s t a t e V

? D

C % g e t s a l e s ( 2 E , < )


I B M D B 2 ,



+: © 2010 IBM Corporation


D a t a b a s e O b j e c t s 7 a c . a g e s

& a c . a g e i s a n o b " e # t t h a t # o n t a i n s i n % o r m a t i o n n e e e t o p r o # e s s S =

s t a t e m e n t s a s s o # i a t e w i t h a s o u r # e # o e % i l e o % a n a p p l i # a t i o n p r o g r a m D u r i n g t h e r e * c o m i l e r o c e s s *

- a s o u r # e # o e % i l e # o n t a i n i n g e m b e e S = s t a t e m e n t s i s # o n ) e r t e

i n t o a s o u r # e # o e % i l e t h a t i s m a e u p e n t i r e l . o % h i g h K l e ) e l p r o g r a m m i n g

l a n g u a g e s t a t e m e n t s

- & t t h e s a m e t i m e * a # o r r e s p o n i n g p a # k a g e t h a t # o n t a i n s t h e a # # e s s

p l a n s t h a t w i l l b e u s e t o p r o # e s s e a # h S = s t a t e m e n t e m b e e i n t h e

s o u r # e # o e % i l e i s a l s o r o d u c e d

- - h i s p a # k a g e m u s t r e s i e i n a D B 2 a t a b a s e t h a t # o n t a i n s t h e a t a

o b " e # t s r e % e r e n # e b . t h e p a # k a g e b e % o r e t h e # o r r e s p o n i n g a p p l i # a t i o n# a n b e e 3 e # u t e a g a i n s t t h a t a t a b a s e

- h e p r o # e s s o % # r e a t i n g a n s t o r i n g a p a # k a g e i n a D B 2 a t a b a s e i s k n o w n

a s b i n d i n g * a n b . e % a u l t * p a # k a g e s a r e a u t o m a t i # a l l . b o u n t o a

a t a b a s e u r i n g t h e p r e # o m p i l e p r o # e s s

Information Management Ecos stem Partnerships



Information Management

Information Management Ecosystem PartnershipsIBM Canada Lab

Summer/Fall 2010Questions?

E-mail: [email protected]: “DB2 Academic Wo!sho"#

1.4 - working with databases and database objects.odp

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