Informatica INTERVIEW QUESTION & ANSWERS
| 26. |
What is Operational Data Store? |
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Operational Data Store (ODS) is a hybrid data architecture to cover the requirements for both analytical and operational tasks. |
| 27. |
What is the differenece between star schema and snowflake schema? |
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The star schema consists of a fact table with a single table for each dimension. The snowflake schema is a variation on the star schema in which the dimensional tables from a star schema are organized into a hierarchy by normalizing them. A fact constellation is a set of fact tables that share some dimension tables. |
| 28. |
What is data staging? |
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Data staging is the process of transferring the data from the data sources (operational systems) into the target database of the data warehouse. |
| 29. |
What is a session? |
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A session is a set of instructions that describes how and when to move data from sources to targets. |
| 30. |
What is mapping? |
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A mapping is a set of source and target definitions linked by transformation objects that define the rules for data transformation. |
