informatica faq-7
40.Why we use stored procedure transformation?
For populating and maintaining data bases.
42.What r the types of data that passes between informatica server and stored procedure?
3 types of data
Input/Out put parameters
Return Values
Status code.
43.What is the status code?
Status code provides error handling for the informatica server during the session.The stored procedure issues a status code that notifies whether or not stored procedure completed sucessfully.This value can not seen by the user.It only used by the informatica server to determine whether to continue running the session or stop.
44. What is source qualifier transformation?
When U add a relational or a flat file source definition to a maping,U need to connect it to
a source qualifer transformation.The source qualifier transformation represnets the records
that the informatica server reads when it runs a session.
45.What r the tasks that source qualifier performs?
Join data originating from same source data base.
Filter records when the informatica server reads source data.
Specify an outer join rather than the default inner join
specify sorted records.
Select only distinct values from the source.
Creating custom query to issue a special SELECT statement for the informatica server to read
source data.
46. What is the target load order?
U specify the target loadorder based on source qualifiers in a maping.If u have the multiple
source qualifiers connected to the multiple targets,U can designatethe order in which informatica
server loads data into the targets.
47.What is the default join that source qualifier provides?
Inner equi join.
48. What r the basic needs to join two sources in a source qualifier?
Two sources should have primary and Foreign key relation ships.
Two sources should have matching data types.
49.what is update strategy transformation ?
This transformation is used to maintain the history data or just most recent changes in to target
table.
50.Describe two levels in which update strategy transformation sets?
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.
51.What is the default source option for update stratgey transformation?
Data driven.
52. What is Datadriven?
The informatica server follows instructions coded into update strategy transformations with
in the session maping determine how to flag records for insert,update,,delete or reject
If u do not choose data driven option setting,the informatica server ignores all update strategy
transformations in the mapping.
53.What r the options in the target session of update strategy transsformatioin?
Insert
Delete
Update
Update as update
Update as insert
Update esle insert
Truncate table
54. What r the types of maping wizards that r to be provided in Informatica?
The Designer provides two mapping wizards to help you create mappings quickly and easily. Both wizards are designed to create mappings for loading and maintaining star schemas, a series of dimensions related to a central fact table.
Getting Started Wizard. Creates mappings to load static fact and dimension tables, as well as slowly growing dimension tables.
Slowly Changing Dimensions Wizard. Creates mappings to load slowly changing dimension tables based on the amount of historical dimension data you want to keep and the method you choose to handle historical dimension data.
55. What r the types of maping in Getting Started Wizard?
Simple Pass through maping :
Loads a static fact or dimension table by inserting all rows. Use this mapping when you want to drop all existing data from your table before loading new data.
Slowly Growing target :
Loads a slowly growing fact or dimension table by inserting new rows. Use this mapping to load new data when existing data does not require updates.
56. What r the mapings that we use for slowly changing dimension table?
Type1: Rows containing changes to existing dimensions are updated in the target by overwriting the existing dimension. In the Type 1 Dimension mapping, all rows contain current dimension data.
Use the Type 1 Dimension mapping to update a slowly changing dimension table when you do not need to keep any previous versions of dimensions in the table.
Type 2: The Type 2 Dimension Data mapping inserts both new and changed dimensions into the target. Changes are tracked in the target table by versioning the primary key and creating a version number for each dimension in the table.
Use the Type 2 Dimension/Version Data mapping to update a slowly changing dimension table when you want to keep a full history of dimension data in the table. Version numbers and versioned primary keys track the order of changes to each dimension.
Type 3: The Type 3 Dimension mapping filters source rows based on user-defined comparisons and inserts only those found to be new dimensions to the target. Rows containing changes to existing dimensions are updated in the target. When updating an existing dimension, the Informatica Server saves existing data in different columns of the same row and replaces the existing data with the updates
57.What r the different types of Type2 dimension maping?
Type2 Dimension/Version Data Maping: In this maping the updated dimension in the source will gets inserted in target along with a new version number.And newly added dimension
in source will inserted into target with a primary key.
Type2 Dimension/Flag current Maping: This maping is also used for slowly changing dimensions.In addition it creates a flag value for changed or new dimension.
Flag indiactes the dimension is new or newlyupdated.Recent dimensions will gets saved with cuurent flag value 1. And updated dimensions r saved with the value 0.
Type2 Dimension/Effective Date Range Maping: This is also one flavour of Type2 maping used for slowly changing dimensions.This maping also inserts both new and changed dimensions in to the target.And changes r tracked by the effective date range for each version of each dimension.
58.How can u recognise whether or not the newly added rows in the source r gets insert in the target ?
In the Type2 maping we have three options to recognise the newly added rows
Version number
Flagvalue
Effective date Range
59. What r two types of processes that informatica runs the session?
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.
For populating and maintaining data bases.
42.What r the types of data that passes between informatica server and stored procedure?
3 types of data
Input/Out put parameters
Return Values
Status code.
43.What is the status code?
Status code provides error handling for the informatica server during the session.The stored procedure issues a status code that notifies whether or not stored procedure completed sucessfully.This value can not seen by the user.It only used by the informatica server to determine whether to continue running the session or stop.
44. What is source qualifier transformation?
When U add a relational or a flat file source definition to a maping,U need to connect it to
a source qualifer transformation.The source qualifier transformation represnets the records
that the informatica server reads when it runs a session.
45.What r the tasks that source qualifier performs?
Join data originating from same source data base.
Filter records when the informatica server reads source data.
Specify an outer join rather than the default inner join
specify sorted records.
Select only distinct values from the source.
Creating custom query to issue a special SELECT statement for the informatica server to read
source data.
46. What is the target load order?
U specify the target loadorder based on source qualifiers in a maping.If u have the multiple
source qualifiers connected to the multiple targets,U can designatethe order in which informatica
server loads data into the targets.
47.What is the default join that source qualifier provides?
Inner equi join.
48. What r the basic needs to join two sources in a source qualifier?
Two sources should have primary and Foreign key relation ships.
Two sources should have matching data types.
49.what is update strategy transformation ?
This transformation is used to maintain the history data or just most recent changes in to target
table.
50.Describe two levels in which update strategy transformation sets?
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.
51.What is the default source option for update stratgey transformation?
Data driven.
52. What is Datadriven?
The informatica server follows instructions coded into update strategy transformations with
in the session maping determine how to flag records for insert,update,,delete or reject
If u do not choose data driven option setting,the informatica server ignores all update strategy
transformations in the mapping.
53.What r the options in the target session of update strategy transsformatioin?
Insert
Delete
Update
Update as update
Update as insert
Update esle insert
Truncate table
54. What r the types of maping wizards that r to be provided in Informatica?
The Designer provides two mapping wizards to help you create mappings quickly and easily. Both wizards are designed to create mappings for loading and maintaining star schemas, a series of dimensions related to a central fact table.
Getting Started Wizard. Creates mappings to load static fact and dimension tables, as well as slowly growing dimension tables.
Slowly Changing Dimensions Wizard. Creates mappings to load slowly changing dimension tables based on the amount of historical dimension data you want to keep and the method you choose to handle historical dimension data.
55. What r the types of maping in Getting Started Wizard?
Simple Pass through maping :
Loads a static fact or dimension table by inserting all rows. Use this mapping when you want to drop all existing data from your table before loading new data.
Slowly Growing target :
Loads a slowly growing fact or dimension table by inserting new rows. Use this mapping to load new data when existing data does not require updates.
56. What r the mapings that we use for slowly changing dimension table?
Type1: Rows containing changes to existing dimensions are updated in the target by overwriting the existing dimension. In the Type 1 Dimension mapping, all rows contain current dimension data.
Use the Type 1 Dimension mapping to update a slowly changing dimension table when you do not need to keep any previous versions of dimensions in the table.
Type 2: The Type 2 Dimension Data mapping inserts both new and changed dimensions into the target. Changes are tracked in the target table by versioning the primary key and creating a version number for each dimension in the table.
Use the Type 2 Dimension/Version Data mapping to update a slowly changing dimension table when you want to keep a full history of dimension data in the table. Version numbers and versioned primary keys track the order of changes to each dimension.
Type 3: The Type 3 Dimension mapping filters source rows based on user-defined comparisons and inserts only those found to be new dimensions to the target. Rows containing changes to existing dimensions are updated in the target. When updating an existing dimension, the Informatica Server saves existing data in different columns of the same row and replaces the existing data with the updates
57.What r the different types of Type2 dimension maping?
Type2 Dimension/Version Data Maping: In this maping the updated dimension in the source will gets inserted in target along with a new version number.And newly added dimension
in source will inserted into target with a primary key.
Type2 Dimension/Flag current Maping: This maping is also used for slowly changing dimensions.In addition it creates a flag value for changed or new dimension.
Flag indiactes the dimension is new or newlyupdated.Recent dimensions will gets saved with cuurent flag value 1. And updated dimensions r saved with the value 0.
Type2 Dimension/Effective Date Range Maping: This is also one flavour of Type2 maping used for slowly changing dimensions.This maping also inserts both new and changed dimensions in to the target.And changes r tracked by the effective date range for each version of each dimension.
58.How can u recognise whether or not the newly added rows in the source r gets insert in the target ?
In the Type2 maping we have three options to recognise the newly added rows
Version number
Flagvalue
Effective date Range
59. What r two types of processes that informatica runs the session?
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.
posted by dwhfaq | 11:03 AM
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