Q.What are the different types of transformation available in informatica. and what are the mostly used ones among them?
A.Mainly there are two types of tranformation.
1.Active TransformationAn active transformation can change the number of rows that pass through it from source to target i.e it eliminates rows that do not meet the condition in transformation.
A.Mainly there are two types of tranformation.
1.Active TransformationAn active transformation can change the number of rows that pass through it from source to target i.e it eliminates rows that do not meet the condition in transformation.
2.Passive TransformationA passive transformation does not change the number of rows that pass through it i.e it passes all rows through the transformation.Transformations can be Connected or UnConnected. Connected TransformationConnected transformation is connected to other transformations or directly to target table in the mapping.UnConnected TransformationAn unconnected transformation is not connected to other transformations in the mapping. It is called within another transformation, and returns a value to that transformation.list of Transformations available in Informatica:
a.source qualifier Tranformation
b.Expression Transformation
a.source qualifier Tranformation
b.Expression Transformation
3.Filter Transformation
4.Joiner Transformation
5.Lookup Transformation
6.Normalizer Transformation
7.Rank Transformation
8.Router Transformation
9.Sequence Generator Transformation
10.Stored Procedure Transformation
11.Sorter Transformation
12.Update Strategy Transformation
13.Aggregator Transformation
14.XML Source Qualifier Transformation
15.Advanced External Procedure Transformation
16.External Transformation
17.custom tranformationMostly use of particular tranformation depend upon the requirement.
4.Joiner Transformation
5.Lookup Transformation
6.Normalizer Transformation
7.Rank Transformation
8.Router Transformation
9.Sequence Generator Transformation
10.Stored Procedure Transformation
11.Sorter Transformation
12.Update Strategy Transformation
13.Aggregator Transformation
14.XML Source Qualifier Transformation
15.Advanced External Procedure Transformation
16.External Transformation
17.custom tranformationMostly use of particular tranformation depend upon the requirement.
Q.What are two types of processes that informatica runs the session?
A.Load manager Process: Starts the session, creates the DTM process, and sends post-session email when the session completes.The DTM process. Creates threads to initialize the session, read, write, and transform data, and handle pre- and post-session operations.How can we store previous session logs
ust run the session in time stamp mode then automatically session log will not overwrite current session log.
A.Load manager Process: Starts the session, creates the DTM process, and sends post-session email when the session completes.The DTM process. Creates threads to initialize the session, read, write, and transform data, and handle pre- and post-session operations.How can we store previous session logs
ust run the session in time stamp mode then automatically session log will not overwrite current session log.
Q.What is meant by Junk Attribute in Informatica?
A.Junk Dimension A Dimension is called junk dimension if it contains attribute which are rarely changed ormodified. example In Banking Domain , we can fetch four attributes accounting to a junk dimensions like from the Overall_Transaction_master table tput flag tcmp flag del flag advance flag all these attributes can be a part of a junk dimensions
A.Junk Dimension A Dimension is called junk dimension if it contains attribute which are rarely changed ormodified. example In Banking Domain , we can fetch four attributes accounting to a junk dimensions like from the Overall_Transaction_master table tput flag tcmp flag del flag advance flag all these attributes can be a part of a junk dimensions
Q.In a joiner trasformation, you should specify the source with fewer rows as the master source. Why?
A.Joiner transformation compares each row of the master source against the detail source. The fewer unique rows in the master, the fewer iterations of the join comparison occur, which speeds the join process.
A.Joiner transformation compares each row of the master source against the detail source. The fewer unique rows in the master, the fewer iterations of the join comparison occur, which speeds the join process.
Q.What are the tasks that source qualifier performs?
A.
1.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.
2.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.
3.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.
4.Specify sorted ports. If you specify a number for sorted ports, the Informatica Server adds an ORDER BY clause to the default SQL query.
5.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.
6.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.
A.
1.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.
2.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.
3.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.
4.Specify sorted ports. If you specify a number for sorted ports, the Informatica Server adds an ORDER BY clause to the default SQL query.
5.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.
6.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.
Q.How to join two tables without using the Joiner Transformation.
A.It's possible to join the two or more tables by using source qualifier.But provided the tables should have relationship.
When u drag n drop the tables u will getting the source qualifier for each table.Delete all the source qualifiers.Add a common source qualifier for all.Right click on the source qualifier u will find EDIT click on it.Click on the properties tab,u will find sql query in that u can write ur sqls
A.It's possible to join the two or more tables by using source qualifier.But provided the tables should have relationship.
When u drag n drop the tables u will getting the source qualifier for each table.Delete all the source qualifiers.Add a common source qualifier for all.Right click on the source qualifier u will find EDIT click on it.Click on the properties tab,u will find sql query in that u can write ur sqls
Q.If you want to create indexes after the load process which transformation you choose?
A.Its usually not done in the mapping(transformation) level. Its done in session level. Create a command task which will execute a shell script (if Unix) or any other scripts which contains the create index command. Use this command task in the workflow after the session or else, You can create it with a post session command.
A.Its usually not done in the mapping(transformation) level. Its done in session level. Create a command task which will execute a shell script (if Unix) or any other scripts which contains the create index command. Use this command task in the workflow after the session or else, You can create it with a post session command.
Q.What is the use of incremental aggregation? Explain me in brief with an example.
a.Its a session option. when the informatica server performs incremental aggregation.It passes new source data through the mapping and uses historical chache data to perform new aggregation caluculations incrementaly. for performance we will use it.
a.Its a session option. when the informatica server performs incremental aggregation.It passes new source data through the mapping and uses historical chache data to perform new aggregation caluculations incrementaly. for performance we will use it.
Q.What happens if you try to create a shortcut to a non-shared folder?
A.It only creates a copy of it..
A.It only creates a copy of it..
Q.What is metadata reporter?
A.It is a web based application that enables you to run reports againist repository metadata.With a meta data reporter,You can access information about U’r repository with out having knowledge of sql,transformation language or underlying tables in the repository.
A.It is a web based application that enables you to run reports againist repository metadata.With a meta data reporter,You can access information about U’r repository with out having knowledge of sql,transformation language or underlying tables in the repository.
Q.What is polling?
A.It displays the updated information about the session in the monitor window. The monitor window displays the status of each session when you poll the informatica server.
A.It displays the updated information about the session in the monitor window. The monitor window displays the status of each session when you poll the informatica server.
Q.How do we estimate the number of partitons that a mapping really requires? Is it dependent on the machine configuration?
A.It depends upon the informatica version we r using. suppose if we r using informatica 6 it supports only 32 partitions where as informatica 7 supports 64 partitions.
A.It depends upon the informatica version we r using. suppose if we r using informatica 6 it supports only 32 partitions where as informatica 7 supports 64 partitions.
Q.How do you decide whether you need ti do aggregations at database level or at Informatica level?
A.It depends upon our requirment only.If you have good processing database you can create aggregation table or view at database level else its better to use informatica. Here i'm explaing why we need to use informatica.what ever it may be informatica is a thrid party tool, so it will take more time to process aggregation compared to the database, but in Informatica an option we called "Incremental aggregation" which will help you to update the current values with current values +new values. No necessary to process entire values again and again. Unless this can be done if nobody deleted that cache files. If that happend total aggregation we need to execute on informatica also.In database we don't have Incremental aggregation facility.
A.It depends upon our requirment only.If you have good processing database you can create aggregation table or view at database level else its better to use informatica. Here i'm explaing why we need to use informatica.what ever it may be informatica is a thrid party tool, so it will take more time to process aggregation compared to the database, but in Informatica an option we called "Incremental aggregation" which will help you to update the current values with current values +new values. No necessary to process entire values again and again. Unless this can be done if nobody deleted that cache files. If that happend total aggregation we need to execute on informatica also.In database we don't have Incremental aggregation facility.
Q.Discuss which is better among incremental load, Normal Load and Bulk load
A.It depends on the requirement. Otherwise Incremental load which can be better as it takes onle that data which is not available previously on the target.
A.It depends on the requirement. Otherwise Incremental load which can be better as it takes onle that data which is not available previously on the target.
Q.What is IQD file?
A.IQD file is nothing but Impromptu Query Definetion,This file is maily used in Cognos Impromptu tool after creating a imr( report) we save the imr as IQD file which is used while creating a cube in power play transformer.In data source type we select Impromptu Query Definetion.
A.IQD file is nothing but Impromptu Query Definetion,This file is maily used in Cognos Impromptu tool after creating a imr( report) we save the imr as IQD file which is used while creating a cube in power play transformer.In data source type we select Impromptu Query Definetion.
Q.Which objects are required by the debugger to create a valid debug session?
A.Intially the session should be valid session.source, target, lookups, expressions should be availble, min 1 break point should be available for debugger to debug your session.
A.Intially the session should be valid session.source, target, lookups, expressions should be availble, min 1 break point should be available for debugger to debug your session.
Q.What are the options in the target session of update strategy transsformatioin?
A.
1.Insert
2.Delete
3.Update
4.Update as update
5.Update as insert
6.Update esle insert
7.Truncate table
A.
1.Insert
2.Delete
3.Update
4.Update as update
5.Update as insert
6.Update esle insert
7.Truncate table
Q.What are the types of groups in Router transformation?
A.
1.Input group
2.Output group
The designer copies property information from the input ports of the input group to create a set of output ports for each output group.
Two types of output groups:-
1.User defined groups
2.Default group.
You can not modify or delete default groups.
A.
1.Input group
2.Output group
The designer copies property information from the input ports of the input group to create a set of output ports for each output group.
Two types of output groups:-
1.User defined groups
2.Default group.
You can not modify or delete default groups.
Q.What is the default join that source qualifier provides?
A.Inner equi join.
A.Inner equi join.
Q.Define informatica repository?
A.Infromatica 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 application and tools access. The informatica client and server access the repository to save and retrieve metadata.
Which tool U use to create and manage sessions and batches and to monitor and stop the informatica server?
Informatica Workflow Managar and Informatica Worlflow Monitor
A.Infromatica 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 application and tools access. The informatica client and server access the repository to save and retrieve metadata.
Which tool U use to create and manage sessions and batches and to monitor and stop the informatica server?
Informatica Workflow Managar and Informatica Worlflow Monitor
Q.What is the process flow of informatica,
A.Informatica is a ETL tool.used for the Extraction,Transformation and Loadind of data.This tool is used to Extract the data from different Data Bases and then we can do the required transfermation like data type conversions,doing some aggregations,ordering,filtering and so on.After that we can load the transformed data into our database,which will be used for the Bussiness Decissions.
A.Informatica is a ETL tool.used for the Extraction,Transformation and Loadind of data.This tool is used to Extract the data from different Data Bases and then we can do the required transfermation like data type conversions,doing some aggregations,ordering,filtering and so on.After that we can load the transformed data into our database,which will be used for the Bussiness Decissions.
Q.Can anyone explain about incremental aggregation with an example?
A.Incremental aggregation is specially used for tune the performance of the aggregator. It captures the change each time (incrementally) you run the transformation and then performs the aggregation function to the changed rows and not to the entire rows. This improves the performance because you are not reading the entire source, each time you run the session.
A.Incremental aggregation is specially used for tune the performance of the aggregator. It captures the change each time (incrementally) you run the transformation and then performs the aggregation function to the changed rows and not to the entire rows. This improves the performance because you are not reading the entire source, each time you run the session.
Q.How can you recognise whether or not the newly added rows in the source are gets insert in the target?
A.In the Type2 maping we have three options to recognise the newly added rows
1.Version number
2.Flagvalue
3.Effective date Range.
A.In the Type2 maping we have three options to recognise the newly added rows
1.Version number
2.Flagvalue
3.Effective date Range.
Q.What is difference between dimention table and fact table and what are different dimention tables and fact tables
A.In the fact table contain measurable data and less columns and meny rows,It contains primarykey.
Diffrent types of fact tables:additive,non additive, semi additive
In the dimensions table contain textual descrption of data and also contain meny columns,less rows.It contains primary key.
A.In the fact table contain measurable data and less columns and meny rows,It contains primarykey.
Diffrent types of fact tables:additive,non additive, semi additive
In the dimensions table contain textual descrption of data and also contain meny columns,less rows.It contains primary key.
Q.How to export mappings to the production environment?
A.In the designer go to the main menu and one can see the export/import options.Import the exported mapping in to the production repository with replace options.
A.In the designer go to the main menu and one can see the export/import options.Import the exported mapping in to the production repository with replace options.
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