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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.
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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.
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.
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.
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
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
Import from Database Use ODBC connection for importing from database
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: Relational source definition Flat file source definition COBOL source definition Manually create a target definition. Create and design a target definition in the Warehouse Designer.
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 • 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.
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.