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Introduction to

Informatica PowerCenter


Data Warehousing


Data warehousing is the entire
process of data extraction,
transformation, and loading of data to
the warehouse and the access of the
data by end users and applications

Data Mart


A data mart stores data for a limited
number of subject areas, such as
marketing and sales data. It is used
to support specific applications.


An independent data mart is created
directly from source systems.


A dependent data mart is populated
from a data warehouse.

Prod
Mkt
HR
Fi n
Acctg
Data Sources
Transaction Data
IBM
IMS
VSAM
Oracle
Sybase
ETL Software
Data Stores
Data Analysis
Tools and
Applications
Users
Other Internal Data
ERP
SAP
Clickstream
Infor mix
Web Data
External Data
Demographic
Harte-
Hanks
S
T
A
G
I
N
G
A
R
E
A
O
P
E
R
A
T
I
O
N
A
L
D
A
T
A
S
T
O
R
E
Ascential
Ext ract
Sagent
SAS
Cl ean/Scrub
Transform
Fi rst logic
Load
Informatica
Dat a Mart s
Teradata
IBM
Dat a
Warehouse
Meta
Dat a
Fi nance
Marketing
Sales
Essbase
Microsoft
ANALYSTS
MANAGERS
EXECUTIVES
OPERATIONAL
PERSONNEL
CUSTOMERS/
SUPPLIERS
SQL
Cognos
SAS
Queri es,Reporting,
DSS/EIS,
Data Mining
Micro Strat egy
Si ebel
Busi ness
Objects
Web
Browser
Need For ETL Tool

Data Extraction



Often performed by COBOL routines

(not recommended because of high program
maintenance and no automatically generated
meta data)


Sometimes source data is copied to the
target database using the replication
capabilities of standard RDBMS (not
recommended because of “dirty data” in the
source systems)


Increasing performed by specialized ETL
software


Sample ETL Tools


DataStage from Ascential Software


SAS System from SAS Institute


Informatica


Data Integrator From BO


Hummingbird Genio Suite from Hummingbird
Communications


Oracle Express


Abinito


Decision Stream From Cognos


MS
-
DTS from Microsoft


Components Of Informatica



Repository Manager




Designer




Workflow Manager

Informatica provides the following integrated
components:



Informatica

repository
.

The

Informatica

repository

is

at

the

center

of

the

Informatica

suite
.

You

create

a

set

of

metadata

tables

within

the

repository

database

that

the

Informatica

applications

and

tools

access
.

The

Informatica

Client

and

Server

access

the

repository

to

save

and

retrieve

metadata
.



Informatica

Client
.

Use

the

Informatica

Client

to

manage

users,

define

sources

and

targets,

build

mappings

and

mapplets

with

the

transformation

logic,

and

create

sessions

to

run

the

mapping

logic
.

The

Informatica

Client

has

three

client

applications
:

Repository

Manager,

Designer,

and

Workflow

Manager
.



Informatica

Server
.

The

Informatica

Server

extracts

the

source

data,

performs

the

data

transformation,

and

loads

the

transformed

data

into

the

targets
.


Architecture

Process Flow


Informatica Server moves the data from source to target
based on the workflow and metadata stored in the
repository.


A workflow is a set of instructions how and when to run
the task related to ETL.


Informatica server runs workflow according to the
conditional links connecting tasks.


Session is type of workflow task which describes how to
move the data between source and target using a
mapping.


Mapping is a set of source and target definitions linked
by transformation objects that define the rules for data
transformation.

Sources


Power Mart and Power Center access the following sources:



Relational.

Oracle, Sybase, Informix, IBM DB2, Microsoft SQL
Server, and Teradata.



File
. Fixed and delimited flat file, COBOL file, and XML.



Extended
. If you use Power Center, you can purchase
additional Power Connect products to access business sources
such as PeopleSoft, SAP R/3, Siebel, and IBM MQSeries.



Mainframe
. If you use Power Center, you can purchase Power
Connect for IBM DB2 for faster access to IBM DB2 on MVS.



Other
. Microsoft Excel and Access
.

Targets

Power Mart and Power Center can load data into the
following targets:



Relational
. Oracle, Sybase, Sybase IQ, Informix, IBM DB2,
Microsoft SQL Server, and Teradata.



File
. Fixed and delimited flat files and XML.



Extended
. If you use Power Center, you can purchase an
integration server to load data into SAP BW. You can also
purchase Power Connect for IBM MQSeries to load data into
IBM MQSeries message queues.



Other
. Microsoft Access
.



You can load data into targets using ODBC or native
drivers, FTP, or external loaders.

General Flow of Informatica


Step 1: Creating Repository ,creating folders ,Creating
users and assign permission in Repository Manager, so
as to work in the client tools
.



Step 2:Connecting to the repository from the designer.
importing source and target tables , creation of
mappings
.



Step 3 : Creation of Workflow through workflow Manager
which has different tasks connected between them. In
that ,session is the task which is pointing to a mapping
created in the designer.

Repository


The

Informatica

repository

is

a

set

of

tables

that

stores

the

metadata

you

create

using

the

Informatica

Client

tools
.

You

create

a

database

for

the

repository,

and

then

use

the

Repository

Manager

to

create

the

metadata

tables

in

the

database
.



You

add

metadata

to

the

repository

tables

when

you

perform

tasks

in

the

Informatica

Client

application

such

as

creating

users,

analyzing

sources,

developing

mappings

or

mapplets,

or

creating

sessions
.

The

Informatica

Server

reads

metadata

created

in

the

Client

application

when

you

run

a

session
.

The

Informatica

Server

also

creates

metadata

such

as

start

and

finish

times

of

a

session

or

session

status
.








Contd

:
-


Repository Contd..


When

you

use

Power

Center,

you

can

develop

global

and

local

repository

to

share

metadata
:



Global

repository
.

The

global

repository

is

the

hub

of

the

domain
.

Use

the

global

repository

to

store

common

objects

that

multiple

developers

can

use

through

shortcuts
.

These

objects

may

include

operational

or

application

source

definitions,

reusable

transformations,

mapplets,

and

mappings
.


Local

repositories
.

A

local

repository

is

within

a

domain

that

is

not

the

global

repository
.

Use

local

repositories

for

development
.

From

a

local

repository,

you

can

create

shortcuts

to

objects

in

shared

folders

in

the

global

repository
.

These

objects

typically

include

source

definitions,

common

dimensions

and

lookups,

and

enterprise

standard

transformations
.

You

can

also

create

copies

of

objects

in

non
-
shared

folders
.

Repository Architecture




Repository Client


Repository Server


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


Repository Agent


Repository Database

Creating a Repository

To

create

Repository



1
.


Launch

the

Repository

Manager

by

choosing

Programs
-
Power

Center

(or


Power

Mart)

Client
-
Repository

Manager

from

the

Start

Menu
.




2
.


In

the

Repository

Manager,

choose

Repository
-
Create

Repository
.



Note
:

You

must

be

running

the

Repository

Manager

in

Administrator

mode

to

see

the

Create

Repository

option

on

the

menu
.

Administrator

mode

is

the

default

when

you

install

the

program
.



3
.


In

the

Create

Repository

dialog

box,

specify

the

name

of

the

new


repository,

as

well

as

the

parameters

needed

to

connect

to

the

repository


database

through

ODBC
.

Working with Repository..



By default 2 users will be created in the repository .



Database user used to connect to the repository.



Administrator User.


By default 2 Groups will be created



Public


Administrators.


These groups and users cannot be deleted from the
repository . The administrator group has only read
privilege for other user groups.


Working with Repository contd..

Informatica

tools

include

two

basic

types

of

security
:



Privileges
.

Repository
-
wide

security

that

controls

which

task

or

set

of

tasks

a

single

user

or

group

of

users

can

access
.

Examples

of

these

are

Use

Designer,

Browse

repository

,

Session

operator

etc
.




Permissions
.

Security

assigned

to

individual

folders

within

the

repository
.

You

can

perform

various

tasks

for

each

privilege
.



Ex

:
-

Read

,

Write

and

Execute
.


Folders


Folders

provide

a

way

to

organize

and

store

all

metadata

in

the

repository,

including

mappings,

schemas,

and

sessions
.

Folders

are

designed

to

be

flexible,

to

help

you

organize

your

data

warehouse

logically
.

Each

folder

has

a

set

of

properties

you

can

configure

to

define

how

users

access

the

folder
.

For

example,

you

can

create

a

folder

that

allows

all

repository

users

to

see

objects

within

the

folder,

but

not

to

edit

them
.

Or

you

can

create

a

folder

that

allows

users

to

share

objects

within

the

folder
.



Shared

Folders


When

you

create

a

folder,

you

can

configure

it

as

a

shared

folder
.

Shared

folders

allow

users

to

create

shortcuts

to

objects

in

the

folder
.

If

you

have

reusable

transformation

that

you

want

to

use

in

several

mappings

or

across

multiple

folders,

you

can

place

the

object

in

a

shared

folder
.



For

example,

you

may

have

a

reusable

Expression

transformation

that

calculates

sales

commissions
.

You

can

then

use

the

object

in

other

folders

by

creating

a

shortcut

to

the

object
.


Folder Permissions

Permissions

allow

repository

users

to

perform

tasks

within

a

folder
.

With

folder

permissions,

you

can

control

user

access

to

the

folder,

and

the

tasks

you

permit

them

to

perform
.



Folder permissions work closely with repository privileges.
Privileges grant access to specific tasks while permissions
grant access to specific folders with read, write, and
execute qualifiers.



However, any user with the Super User privilege can
perform all tasks across all folders in the repository. Folders
have the following types of permissions:



Read permission
. Allows you to view the folder as well as
objects in the folder.



Write permission
. Allows you to create or edit objects in the
folder.



Execute permission
. Allows you to execute or schedule a
session or batch in the folder.


Creating Folders




Other Features of Repository Manager


Viewing , removing Locks



Adding Repository



Backup and Recovery of Repository



Taking Metadata reports like

Completed Sessions
details

, List of reports on Jobs , session ,
workflow etc



Questions/Comments
?









Designer

Working with Designer


Connecting to the repository using User id
and password.



Accessing the folder



Importing the source and target tables
required for mapping.



Creation of mapping

Tools provided by Designer


Source Analyzer:
Importing Source definitions
for Flat file, XML, COBOL and relational Sources.



Warehouse Designer:
Use to Import or create
target definitions.



Transformation Developer:
Used to create
reusable transformations



Mapplet Designer:
Used to create mapplets



Mapping Designer:
Used to create mappings

Importing Sources

Import from Database

Use ODBC connection for importing from database

Import from File

Creating Targets

You can create target definitions in the Warehouse Designer for file
and relational sources. Create definitions in the following ways:



Import the definition for an existing target.

Import the
target definition from a relational target.



Create a target definition based on a source definition
.
Drag one of the following existing source definitions into the
Warehouse Designer to make a target definition:

o
Relational source definition

o
Flat file source definition

o
COBOL source definition



Manually create a target definition.
Create and design a
target definition in the Warehouse Designer
.



Creating targets

Creation of simple mapping

Creation of simple mapping


Switch to the Mapping Designer.



Choose Mappings
-
Create.



While the workspace may appear blank, in fact it contains a new
mapping without any sources, targets, or transformations.



In the Mapping Name dialog box, enter <Mapping Name> as the name
of the new mapping and click OK.



The naming convention for mappings is m_
MappingName
.




In the Navigator, under the <Repository Name> repository and
<Folder Name> folder, click the Sources node to view source
definitions added to the repository
.


Contd..

Mapping creation Contd..


Click the icon representing the EMPLOYEES source and drag
it into the workbook.


Mapping creation Contd..

The source definition appears in the workspace. The
Designer automatically connects a Source Qualifier
transformation to the source definition. After you add the
target definition, you connect the Source Qualifier to the
target.



Click the Targets icon in the Navigator to open the
list of all target

definitions.


Click and drag the icon for the T_EMPLOYEES target
into the

workspace.


The target definition appears. The final step is
connecting the Source

Qualifier to this target
definition.


Mapping creation Contd..

To Connect the Source Qualifier to Target Definition:

Click once in the middle of the <Column Name> in the Source
Qualifier. Hold down the mouse button, and drag the cursor to the
<Column Name> in the target. Then release the mouse button.
An arrow (called a connector) now appears between the row
columns


Transformations

Transformations


A transformation is a repository object that generates,
modifies, or passes data



The Designer provides a set of transformations that
perform specific functions



Data passes into and out of transformations through
ports that you connect in a mapping or mapplet



Transformations can be active or passive


Transformations


Active transformations


Aggregator

performs aggregate calculations

Filter


serves as a conditional filter

Router


serves as a conditional filter (more than one filters)

Joiner


allows for heterogeneous joins

Source qualifier


represents all data queried from the source




Passive transformations


Expression


performs simple calculations

Lookup


looks up values and passes to other objects

Sequence generator
generates unique ID values

Stored procedure

calls a stored procedure and captures return values

Update strategy

allows for logic to insert, update, delete, or reject



data


Transformations Contd..


Create

the

transformation
.

Create

it

in

the

Mapping

Designer

as

part

of

a


mapping,

in

the

Mapplet

Designer

as

part

of

a

Mapplet,

or

in

the

Transformation

Developer

as

a

reusable

transformation
.




Configure

the

transformation
.

Each

type

of

transformation

has

a

unique

set

of


options

that

you

can

configure
.




Connect

the

transformation

to

other

transformations

and

target

definitions
.


Drag

one

port

to

another

to

connect

them

in

the

mapping

or

Mapplet
.

Expression Transformation


You

can

use

the

Expression

transformations

to

calculate

values

in

a

single

row

before

you

write

to

the

target
.




For

example,

you

might

need

to

adjust

employee

salaries,

concatenate

first

and

last


names,

or

convert

strings

to

numbers
.




You

can

use

the

Expression

transformation

to

perform

any

non
-
aggregate

calculations
.




You

can

also

use

the

Expression

transformation

to

test

conditional

statements

before


you

output

the

results

to

target

tables

or

other

transformations
.


Expression Transformation

Calculating

Values


To

use

the

Expression

transformation

to

calculate

values

for

a

single

row,

you

must

include

the

following

ports
:



Input

or

input/output

ports

for

each

value

used

in

the

calculation
.

For


example,

when


calculating

the

total

price

for

an

order,

determined

by

multiplying

the

unit

price

by

the

quantity


ordered,

the

input

or

input/output

ports
.


One

port

provides

the

unit

price

and

the

other


provides

the

quantity

ordered
.



Output

port

for

the

expression
.

You

enter

the

expression

as

a

configuration


option

for

the


output

port
.

The

return

value

for

the

output

port

needs

to


match

the

return

value

of

the


expression
.


Variable

Port

:

Variable

Port

is

used

like

local

variable

inside

Expression

Transformation

,

which

can

be

used

in

other

calculations

Source Qualifier Transformation

Every

mapping

includes

a

Source

Qualifier

transformation,

representing

all

the

columns

of

information

read

from

a

source

and

temporarily

stored

by

the

Informatica

Server
.

In

addition,

you

can

add

transformations

such

as

a

calculating

sum,

looking

up

a

value,

or

generating

a

unique

ID

that

modify

information

before

it

reaches

the

target
.


Source Qualifier Transformation

When you add a relational or a flat file source definition to a mapping, you need to connect
it to a Source Qualifier transformation.


The Source Qualifier represents the records that the Informatica Server reads when it runs
a session. You can use the Source Qualifier to perform the following tasks:



Join data originating from the same source database.
You can join two or more tables
with primary
-
foreign key relationships by linking the sources to one Source Qualifier.



Filter records when the Informatica Server reads source data.
If you include a filter
condition, the Informatica Server adds a WHERE clause to the default query.



Specify an outer join rather than the default inner join
.

If you include a user
-
defined
join, the Informatica Server replaces the join information specified by the metadata in the
SQL query.



Specify sorted ports
. If you specify a number for sorted ports, the Informatica Server
adds an ORDER BY clause to the default SQL query.



Select only distinct values from the source
.

If you choose Select Distinct, the
Informatica Server adds a SELECT DISTINCT statement to the default SQL query.



Create a custom query

to issue a special SELECT statement for the Informatica Server to
read source data. For example, you might use a custom query to perform aggregate
calculations or execute a stored procedure


Configuring Source Qualifier Transformation

To configure a Source Qualifier:



In the Designer, open a mapping.


Double
-
click the title bar of the Source Qualifier.


In the Edit Transformations dialog box, click
Rename, enter a descriptive name for the
transformation, and click OK. The naming
convention for Source Qualifier transformations is
SQ_
TransformationName
,.


Click the Properties tab.


Configuring Source Qualifier

Option

Description

SQL Query

Defines a custom query that replaces the default query the Informatica Server uses
to read data from sources represented in this Source Qualifier

User
-
Defined
Join

Specifies the condition used to join data from multiple sources represented in the
same Source Qualifier transformation

Source Filter

Specifies the filter condition the Informatica Server applies when querying records.

Number of
Sorted
Ports

Indicates the number of columns used when sorting records queried from relational
sources. If you select this option, the Informatica Server adds an ORDER BY to
the default query when it reads source records. The ORDER BY includes the
number of ports specified, starting from the top of the Source Qualifier.

When selected, the database sort order must match the session sort order.

Tracing Level

Sets the amount of detail included in the session log when you run a session
containing this transformation.

Select Distinct


Specifies if you want to select only unique records. The Informatica Server includes
a SELECT DISTINCT statement if you choose this option.

Joiner Transformation

While

a

Source

Qualifier

transformation

can

join

data

originating

from

a

common

source

database,

the

Joiner

transformation

joins

two

related


heterogeneous

sources

residing

in

different

locations

or

file

systems
.

The

combination

of

sources

can

be

varied
.

You

can

use

the

following

sources
:




Two relational tables existing in separate databases


Two flat files in potentially different file systems


Two different ODBC sources


Two instances of the same XML source


A relational table and a flat file source


A relational table and an XML source


If

two

relational

sources

contain

keys,

then

a

Source

Qualifier

transformation

can

easily

join

the

sources

on

those

keys
.

Joiner

transformations

typically

combine

information

from

two

different

sources

that

do

not

have

matching

keys,

such

as

flat

file

sources
.



The

Joiner

transformation

allows

you

to

join

sources

that

contain

binary

data
.

Creating a Joiner Transformation

To create a Joiner Transformation:




In

the

Mapping

Designer,

choose

Transformation
-
Create
.

Select

the

Joiner

transformation
.

Enter

a

name

for

the

Joiner
.

Click

OK
.

The

naming

convention

for

Joiner

transformations

is

JNR_
TransformationName
.

Enter

a

description

for

the

transformation
.

This

description

appears

in

the

Repository

Manager,

making

it

easier

for

you

or

others

to

understand

or

remember

what

the

transformation

does
.



The

Designer

creates

the

Joiner

transformation
.

Keep

in

mind

that

you

cannot

use

a

Sequence

Generator

or

Update

Strategy

transformation

as

a

source

to

a

Joiner

transformation
.



Drag

all

the

desired

input/output

ports

from

the

first

source

into

the

Joiner

transformation
.

The

Designer

creates

input/output

ports

for

the

source

fields

in

the

Joiner

as

detail

fields

by

default
.

You

can

edit

this

property

later
.



Select

and

drag

all

the

desired

input/output

ports

from

the

second

source

into

the

Joiner

transformation
.

The

Designer

configures

the

second

set

of

source

fields

and

master

fields

by

default
.



Double
-
click

the

title

bar

of

the

Joiner

transformation

to

open

the

Edit

Transformations

dialog

box
.



Select

the

Ports

tab
.



Click

any

box

in

the

M

column

to

switch

the

master/detail

relationship

for

the

sources
.

Change

the

master/detail

relationship

if

necessary

by

selecting

the

master

source

in

the

M

column
.

Creating a Joiner Transformation

Select

the

Condition

tab

and

set

the

condition
.



Configuring Joiner transformation

Joiner Setting

Description

Case
-
Sensitive
String
Comparison

If selected, the Informatica Server uses case
-
sensitive string
comparisons when performing joins on string columns.

Cache Directory

Specifies the directory used to cache master records and the index to
these records. By default, the caches are created in a directory
specified by the server variable $PMCacheDir. If you override the
directory, be sure there is enough disk space on the file system. The
directory can be a mapped or mounted drive.

Join Type

Specifies the type of join: Normal, Master Outer, Detail Outer, or Full
Outer.


Used to look up data in a relational table, view, synonym or Flat
File.


It compares Lookup transformation port values to lookup table
column values based on the lookup condition.

Connected Lookups


Receives input values directly from another transformation in the
pipeline


For each input row, the Informatica Server queries the lookup table
or cache based on the lookup ports and the condition in the
transformation


Passes return values from the query to the next transformation

Un Connected Lookups


Receives input values from an expression using the



:LKP (:LKP.lookup_transformation_name (argument, argument,
...)) reference qualifier to call the lookup and returns one value.


With unconnected Lookups, you can pass multiple input values into
the transformation, but only one column of data out of the
transformation


Lookup Transformation

Lookup Transformation

You

can

configure

the

Lookup

transformation

to

perform

different

types

of


lookups
.

You

can

configure

the

transformation

to

be

connected

or

unconnected,

cached

or

uncached
:




Connected

or

unconnected
.

Connected

and

unconnected

transformations

receive

input

and

send

output

in

different

ways
.




Cached

or

uncached
.

Sometimes

you

can

improve

session

performance

by

caching

the

lookup

table
.

If

you

cache

the

lookup

table,

you

can

choose

to

use

a

dynamic

or

static

cache
.

By

default,

the

lookup

cache

remains

static

and

does

not

change

during


the

session
.

With

a

dynamic

cache,

the

Informatica

Server

inserts

rows

into

the

cache

during

the

session
.

Informatica

recommends

that

you

cache

the

target

table

as

the

lookup
.

This

enables

you

to

look

up

values

in

the

target

and

insert

them

if

they

do

not

exist
.



Diff bet Connected & Unconnected Lookup

Connected lookup

Unconnected lookup


1) Receives input values directly
from


of a
the pipe line transformation
.

Receives input values from the result of
LKP expression within other
transformation.

2)

U can use a dynamic or static cache



U can use a static cache.

3) Cache includes all lookup columns used
in the mapping.

Cache includes all lookup out put ports.

4) Support user defined default values

Does not support user defined default
values

Diff between Static & Dynamic Cache

Static Cache

Dynamic Cache

1)

U can not insert or update the
cache

U can insert rows into the cache as u pass
to the target

2) The Informatica Server does not
update the cache while it processes
the Lookup transformation

The Informatica Server dynamically
inserts data into the lookup cache
and passes data to the target table.

Update Strategy Transformation

When

you

design

your

data

warehouse,

you

need

to

decide

what

type

of

information

to

store

in

targets
.

As

part

of

your

target

table

design,

you

need

to

determine

whether

to

maintain

all

the

historic

data

or

just

the

most

recent

changes
.



For

example,

you

might

have

a

target

table,

T_CUSTOMERS,

that

contains

customer

data
.

When

a

customer

address

changes,

you

may

want

to

save

the

original

address

in

the

table,

instead

of

updating

that

portion

of

the

customer

record
.

In

this

case,

you

would

create

a

new

record

containing

the

updated

address,

and

preserve

the

original

record

with

the

old

customer

address
.

This

illustrates

how

you

might

store

historical

information

in

a

target

table
.

However,

if

you

want

the

T_CUSTOMERS

table

to

be

a

snapshot

of

current

customer

data,

you

would

update

the

existing

customer

record

and

lose

the

original

address
.



The

model

you

choose

constitutes

your

update

strategy
,

how

to

handle

changes

to

existing

records
.

In

Power

Mart

and

Power

Center,

you

set

your

update

strategy

at

two

different

levels
:




Within

a

session
.

When

you

configure

a

session,

you

can

instruct

the

Informatica

Server

to

either

treat

all

records

in

the

same

way

(for

example,

treat

all

records

as

inserts),

or

use

instructions

coded

into

the

session

mapping

to

flag

records

for

different

database

operations
.




Within

a

mapping
.

Within

a

mapping,

you

use

the

Update

Strategy

transformation

to

flag

records

for

insert,

delete,

update,

or

reject
.

Setting up Update Strategy at Session Level

During

session

configuration,

you

can

select

a

single

database

operation

for

all

records
.

For

the

Treat

Rows

As

setting,

you

have

the

following

options
:




Setting

Description

Insert

Treat all records as inserts. If inserting the record violates a primary or
foreign key constraint in the database, the Informatica Server rejects the
record.

Delete

Treat all records as deletes. For each record, if the Informatica Server finds a
corresponding record in the target table (based on the primary key value),
the Informatica Server deletes it. Note that the primary key constraint must
exist in the target definition in the repository.

Update

Treat all records as updates. For each record, the Informatica Server looks for
a matching primary key value in the target table. If it exists, the Informatica
Server updates the record. Again, the primary key constraint must exist in the
target definition.

Data
Driven

The Informatica Server follows instructions coded into Update Strategy
transformations within the session mapping to determine how to flag records
for insert, delete, update, or reject.

If the mapping for the session contains an Update Strategy transformation,
this field is marked Data Driven by default.

If you do not choose Data Driven setting, the Informatica Server ignores all


Update Strategy transformations in the mapping.


Update Strategy Settings


setting you choose depends on your update strategy and the status of data in target tables:


Setting

Use To

Insert

Populate the target tables for the first time, or maintaining a historical
data warehouse. In the latter case, you must set this strategy for the
entire data warehouse, not just a select group of target tables.

Delete

Clear target tables.

Update

Update target tables. You might choose this setting whether your data
warehouse contains historical data or a snapshot. Later, when you
configure how to update individual target tables, you can determine
whether to insert updated records as new records or use the updated
information to modify existing records in the target.

Data
Driven

Exert finer control over how you flag records for insert, delete, update,
or reject. Choose this setting if records destined for the same table
need to be flagged on occasion for one operation (for example,
update), or for a different operation (for example, reject). In addition,
this setting provides the only way you can flag records for reject.