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Data Warehousing Interview Questions and Answers Part: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 (Continued from previous part...) General Datawarehousing Interview Questions and Answers (6) What is real time data-warehousing?
Real-time data warehousing is a combination of two things: 1) real-time activity and 2) data warehousing. Real-time activity is activity that is happening right now. The activity could be anything such as the sale of widgets. Once the activity is complete, there is data about it.
What are slowly changing dimensions?
SCD stands for Slowly changing dimensions. Slowly changing dimensions are of three types
What are Semi-additive and factless facts and in which scenario will you use such kinds of fact tables?
Snapshot facts are semi-additive, while we maintain aggregated facts we go for semi-additive.
Differences between star and snowflake schemas?
Star schema - all dimensions will be linked directly with a fat table. What is a Star Schema? Star schema is a type of organising the tables such that we can retrieve the result from the database easily and fastly in the warehouse environment.Usually a star schema consists of one or more dimension tables around a fact table which looks like a star,so that it got its name. What is a general purpose scheduling tool? The basic purpose of the scheduling tool in a DW Application is to stream line the flow of data from Source To Target at specific time or based on some condition. (Continued on next part...)
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