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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.
Data Sources
ETL Software
S
T
A
G
I
N
G
Transaction Data
Prod
IBM
Mkt
IMS
HR
Fin
VSAM
Ascential
Oracle
Extract
Acctg
Syba se
Other Internal Data
ERP
SAP
Infor mix
SAS
HarteHanks
Users
ANALYSTS
Cognos
Teradata
IBM
Load
Informatica
D
A
T
A
External Data
Demographic
A
R
E
A
O
P
E
R
A
T
I
O
N
A
L
Data Analysis
Tools and
Applications
SQL
Sagent
Web Data
Clickstream
Data Stores
S
T
O
R
E
Clean/Scrub
Trans form
Firstlogic
Data
Warehouse
Data Marts
SAS
MANAGERS
Finance
Essbase
Marketing
Queries,Reporting,
DSS/EIS,
Data Mining
EXECUTIVES
Micro Strategy
Meta
Data
Sales
Microsoft
Siebel
Business
Objects
OPERATIONAL
PERSONNEL
Web
Browser
CUSTOMERS/
SUPPLIERS
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 nonshared 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
Filter
Router
Joiner
Source qualifier

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
performs aggregate calculations
serves as a conditional filter
serves as a conditional filter (more than one filters)
allows for heterogeneous joins
represents all data queried from the source
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
expression.

match
the
return
value
of
the
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.
Lookup Transformation
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
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.