configure database connection to the datasource.
FileSource : To access the remote source file U must configure the FTP connection to the host machine before u create the session.
Hetrogenous : When U’r maping contains more than one source type,the server manager creates a hetrogenous session that displays source options for all types.
What is difference between
partioning of relatonal target and partitioning of file targets?
If u parttion a session with a relational target informatica server creates multiple connectionsto the target database to write target data concurently.If u partition a session with a file target the informatica server creates one target file for each partition.U can configure session properties to merge these target files
what r the transformations that restricts the partitioning of
sessions?
Advanced External procedure tranformation and External procedure transformation: This transformation contains a check box on the properties tab to allow partitioning.Joiner Transformation : U can not partition the master source for a joiner transformation Normalizer Transformation
XML targets.
Performance tuning in Informatica?
The goal of performance tuning is optimize session performance so sessions run during the available load window for the InformaticaServer.Increase the session performance by following.
The performance of the Informatica Server is related to network connections. Data generally moves across a network at less than 1 MB per second, whereas a local disk moves data five to twenty times faster. Thus network connections ofteny affect on session performance.So aviod netwrok connections. Flat files: If u’r flat files stored on a machine other than the informatca server, move those files to the machine that consists of informatica server.
Relational datasources: Minimize the connections to sources ,targets and informatica server to improve session performance.Moving target database into server system may improve session performance.
Staging areas: If u use staging areas u force informatica server to perform multiple datapasses. Removing of staging areas may improve session performance.
U can run the multiple informatica servers againist the same repository.Distibuting the session load to multiple informatica servers may improve session performance.
Run the informatica server in ASCII datamovement mode improves the session performance.Because ASCII datamovement mode stores a character value in one byte.Unicode mode takes 2 bytes to store a character.
If a session joins multiple source tables in one Source Qualifier, optimizing the query may improve performance. Also, single table select statements with an ORDER BY or GROUP BY clause may benefit from optimization such as adding indexes.
We can improve the session performance by configuring the network packet size,which allows
data to cross the network at one time.To do this go to server manger ,choose server configure database connections.
If u r target consists key constraints and indexes u slow the loading of data.To improve the session performance in this case drop constraints and indexes before u run the session and rebuild them after completion of session.
Running a parallel sessions by using concurrent batches will also reduce the time of loading the data.So concurent batches may also increase the session performance.
Partittionig the session improves the session performance by creating multiple connections to sources and targets and loads data in paralel pipe lines.
In some cases if a session contains a aggregator transformation ,u can use incremental aggregation to improve session performance.
Aviod transformation errors to improve the session performance.
If the sessioin containd lookup transformation u can improve the session performance by enabling the look up cache.
If U’r session contains filter transformation ,create that filter transformation nearer to the sources or u can use filter condition in source qualifier.
Aggreagator,Rank and joiner transformation may oftenly decrease the session performance .Because they must group data before processing it.To improve session performance in this case use sorted ports option.
What is difference between maplet and reusable transformation?
Maplet consists of set of transformations that is reusable.A reusable transformation is asingle transformation that can be reusable.
If u create a variables or parameters in maplet that can not be used in another maping or maplet.Unlike the variables that r created in a reusable transformation can be usefull in any other maping or maplet. We can not include source definitions in reusable transformations.But we can add sources to a maplet. Whole transformation logic will be hided in case of maplet.But it is transparent in case of reusable transformation.
We cant use COBOL source qualifier,joiner,normalizer transformations in maplet.Where as we can make them as a reusable transformations.
Define informatica repository?
The Informatica repository is a relational database that stores information, or metadata, used by the Informatica Server and Client tools. Metadata can include information such as mappings describing how to transform source data, sessions indicating when you want the Informatica Server to perform the transformations, and connect strings for sources and targets.The repository also stores administrative information such as usernames and passwords, permissions and privileges, and product version.
Use repository manager to create the repository.The Repository Manager connects to the repository database and runs the code needed to create the repository tables.Thsea tables
stores metadata in specific format the informatica server,client tools use.
What r the types of
metadata that stores in repository?
Following r the types of metadata that stores in the repository Database connections Global objects Mappings Mapplets Multidimensional metadata Reusable transformations Sessions and batches Short cutsSource definitions Target defintions
Transformations• Source definitions. Definitions of database objects (tables, views, synonyms) or files that provide source data. • Target definitions. Definitions of database objects or files that contain the target data. • Multi-dimensional metadata. Target definitions that are configured as cubes and dimensions. • Mappings. A set of source and target definitions along with transformations containing business logic that you build into the transformation. These are the instructions that the Informatica Server uses to transform and move data. • Reusable transformations. Transformations that you can use in multiple mappings. • Mapplets. A set of transformations that you can use in multiple mappings. • Sessions and workflows. Sessions and workflows store information about how and when the
Informatica Server moves data. A workflow is a set of instructions that describes how and when to run tasks related to extracting, transforming, and loading data. A session is a type of task that you can put in a workflow. Each session corresponds to a single mapping
What is power center repository?
The PowerCenter repository allows you to share metadata across repositories to create a data mart domain. In a data mart domain, you can create a single global repository to store metadata used across an enterprise, and a number of local repositories to share the global metadata as needed.• Standalone repository. A repository that functions individually, unrelated and unconnected to other repositories. • Global repository. (PowerCenter only.) The centralized repository in a domain, a group of connected repositories. Each domain can contain one global repository. The global repository can contain common objects to be shared throughout the domain through global shortcuts. • Local repository. (PowerCenteronly.) A repository within a domain that is not the global repository. Each local repository in the domain can connect to the global repository and use objects in its shared folders.
How can u work with
remote database in informatica?did u work directly by using remote connections?
To work with remote datasource u need to connect it with remote connections.But it is notpreferable to work with that remote source directly by using remote connections .Instead u bring that source into U r local machine where informatica server resides.If u work directly with remote source the session performance will decreases by passing less amount of data across the network in a particular time.
You can work with remote,
But you have to
Configure FTP
Connection details
IP address
User authentication
what is incremantal aggregation?
When using incremental aggregation, you apply captured changes in the source to aggregate calculations in a session. If the source changes only incrementally and you can capture changes, you can configure the session to process only those changes. This allows the Informatica Server to update your target incrementally, rather than forcing it to process the entire source and recalculate the same calculations each time you run the session.What r the scheduling
options to run a sesion?
U can shedule a session to run at a given time or intervel,or u can manually run the session.Different options of scheduling
Run only on demand: server runs the session only when user starts session explicitly Run once: Informatica server runs the session only once at a specified date and time. Run every: Informatica server runs the session at regular intervels as u configured.
Customized repeat: Informatica server runs the session at the dats and times secified in the repeat dialog box.
What is tracing level and what r the types of tracing level?
Tracing level represents the amount of information that informatcia server writes in a log file.Types of tracing level Normal
Verbose Verbose init
Verbose data
What is difference between stored procedure transformation and external
procedure transformation?
In case of storedprocedure transformation procedure will be compiled and executed in a relational data source.U need data base connection to import the stored procedure in to u’r maping.Where as in external procedure transformation procedure or function will be executed out side of data source.Ie u need to make it as a DLL to access in u r maping.No need to have data base connection in case of external procedure transformation.Explain about Recovering sessions?
If you stop a session or if an error causes a session to stop, refer to the session and error logs to determine the cause of failure. Correct the errors, and then complete the session. The method you use to complete the session depends on the properties of the mapping, session, and Informatica Server configuration. Use one of the following methods to complete the session:· Run the session again if the Informatica Server has not issued a commit.
· Truncate the target tables and run the session again if the session is not recoverable.
· Consider performing recovery if the Informatica Server has issued at least one commit.