11.What is Operational Data Store?
A ODS is an operational data store which comes as a second layer in a datawarehouse architecture. It has got the characteristics of both OLTP and DSS systems.
12.What is the Difference between OLTP and OLAP?
OLTP is nothing but OnLine Transaction Processing which contains a normalised tables .
But OLAP(Online Analtical Programming) contains the history of OLTP data which is non-volatile acts as a Decisions Support System.
13.How many types of dimensions are available in Informatica?
There are three types of dimensions available are :
Junk dimension Degenerative Dimension Conformed Dimension
14.What is Difference between ER Modeling and Dimensional Modeling?
ER Modeling is used for normalizing the OLTP database design.
Dimesional modeling is used for de-normalizing the ROLAP / MOLAP design.
15.What is the maplet?
Maplet is a set of transformations that you build in the maplet designer and you can use in multiple mapings.
16.What is Session and Batches?
Session: A session is a set of commands that describes the server to move data to the target.
Batch: A Batch is set of tasks that may include one or more numbar of tasks (sessions, ewent wait, email, command, etc).
17.What are slowly changing dimensions?
Dimensions that change overtime are called Slowly Changing Dimensions(SCD).
Slowly Changing Dimension-Type1 : Which has only current records.
Slowly Changing Dimension-Type2 : Which has current records + historical records.
Slowly Changing Dimension-Type3 : Which has current records + one previous records.
18.What are 2 modes of data movement in Informatica Server?
There are two modes of data movement are:
Normal Mode in which for every record a separate DML stmt will be prepared and executed.
Bulk Mode in which for multiple records DML stmt will be preapred and executed thus improves performance.
19.What is the difference between Active and Passive transformation?
Active Transformation:An 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.
Passive Transformation:A passive transformation does not change the number of rows that pass through it i.e it passes all rows through the transformation.
20.What is the difference between connected and unconnected transformation?
Connected Transformation:Connected transformation is connected to other transformations or directly to target table in the mapping.
UnConnected Transformation:An unconnected transformation is not connected to other transformations in the mapping. It is called within another transformation,
and returns a value to that transformation.
A ODS is an operational data store which comes as a second layer in a datawarehouse architecture. It has got the characteristics of both OLTP and DSS systems.
12.What is the Difference between OLTP and OLAP?
OLTP is nothing but OnLine Transaction Processing which contains a normalised tables .
But OLAP(Online Analtical Programming) contains the history of OLTP data which is non-volatile acts as a Decisions Support System.
13.How many types of dimensions are available in Informatica?
There are three types of dimensions available are :
Junk dimension Degenerative Dimension Conformed Dimension
14.What is Difference between ER Modeling and Dimensional Modeling?
ER Modeling is used for normalizing the OLTP database design.
Dimesional modeling is used for de-normalizing the ROLAP / MOLAP design.
15.What is the maplet?
Maplet is a set of transformations that you build in the maplet designer and you can use in multiple mapings.
16.What is Session and Batches?
Session: A session is a set of commands that describes the server to move data to the target.
Batch: A Batch is set of tasks that may include one or more numbar of tasks (sessions, ewent wait, email, command, etc).
17.What are slowly changing dimensions?
Dimensions that change overtime are called Slowly Changing Dimensions(SCD).
Slowly Changing Dimension-Type1 : Which has only current records.
Slowly Changing Dimension-Type2 : Which has current records + historical records.
Slowly Changing Dimension-Type3 : Which has current records + one previous records.
18.What are 2 modes of data movement in Informatica Server?
There are two modes of data movement are:
Normal Mode in which for every record a separate DML stmt will be prepared and executed.
Bulk Mode in which for multiple records DML stmt will be preapred and executed thus improves performance.
19.What is the difference between Active and Passive transformation?
Active Transformation:An 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.
Passive Transformation:A passive transformation does not change the number of rows that pass through it i.e it passes all rows through the transformation.
20.What is the difference between connected and unconnected transformation?
Connected Transformation:Connected transformation is connected to other transformations or directly to target table in the mapping.
UnConnected Transformation:An unconnected transformation is not connected to other transformations in the mapping. It is called within another transformation,
and returns a value to that transformation.
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