Request you to search the forum before posting as this has been discussed in numerous blogs in SCN.
here is a standard difinition of the HANA information views
1) Attribute Views : In the language of SAP Netweaver Business Warehouse , attribute views are like Dimension, but with difference is that attribute views are fully reusable throughout the system and not stuck up to a single model. Simplifying, these are views on one or more table that can be reused for different purpose.
Example : An attribute view "FLIGHT" can show together Airline Code, Airline Connection Number and flight Date into one Object. This attribute view can be used in analytical and calculation views where entities are relevant. Generally attribute views represent master data.But, however technically there is no restriction and its possible to make attribute views on transaction data.
2) Analytical Views : Again, in the language on SAP BW analytical views can be roughly compared with Info Cubes or Info Sets in SAP ERP. As same it joins together one central fact table with contains transaction data to report on, with number of tables or attribute views. You can create variables in an analytical view.
3) Calculation views : Calculation views can be referred as combination of tables, attributes views and analytical views to deliver a complex business requirement. They offer to combine different analytical views into one source of data for reporting.
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