MC	Which statement is NOT CORRECT?	A data mart is a scaled down version of a data warehouse aimed at meeting the information needs of a homogeneous small group of end-users such as a department or business unit (e.g., marketing, finance, logistics, HR, etc.).	incorrect	A virtual data warehouse (sometimes also called a federated database) or virtual data mart contains no physical data but provides a uniform and consolidated single point of access to a set of underlying physical data stores.	incorrect	Dependent data marts pulls their data from a central data warehouse, whereas independent data marts are standalone systems drawing data directly from the operational systems, external sources or a combination of both.	incorrect	A key advantage of virtualization is that it requires no extra processing capacity from the underlying (operational) data stores.	correct	
MC	Which statement is NOT CORRECT?	A fact constellation schema has more than one fact table which can share dimension tables.	incorrect	A factless fact table is a fact table which only contains foreign keys and no measurement data.	incorrect	A snowflake schema normalizes the fact table of a star schema.	correct	Surrogate keys essentially buffer the data warehouse from the operational environment by making it immune to any operational changes.	incorrect	
MC	Which statement is NOT CORRECT?	A data lake stores raw data in its native format, which could be structured, unstructured, or semi-structured. 	incorrect	A virtual data warehouse (sometimes also called a federated database) or virtual data mart contains no physical data but provides a uniform and consolidated single point of access to a set of underlying physical data stores.	incorrect	Multidimensional OLAP (MOLAP) stores the multidimensional data using a Multidimensional DBMS (MDBMS) whereby the data is stored in a multi-dimensional array-based data structure optimized for efficient storage and quick access.	incorrect	A key disadvantage of OLAP is that it does not allow to interactively analyze your data, summarize it and visualize it in various ways.	correct	
MC	Which statement is CORRECT?	A key disadvantage of OLAP is that it does not allow to interactively analyze your data, summarize it and visualize it in various ways.	incorrect	The GROUPING SETS OLAP operator generates a result set equivalent to that generated by an INTERSECT of multiple simple GROUP BY clauses.	incorrect	The key difference between the CUBE and ROLLUP OLAP operators is that the former generates a result set showing the aggregates for a hierarchy of values of the speci?ed attribute types, whereas the latter generates a result set showing the aggregates for all combinations of values of the selected attribute types.	incorrect	Junk dimensions can be defined to efficiently accommodate low cardinality attribute types such as flags or indicators.	correct	
MC	In terms of data manipulation, a data warehouse focusses on...	Insert/Update/Delete/Select statements	incorrect	Insert/Select statements	correct	Select/Update statements	incorrect	Delete statements	incorrect	
MC	Which statement is NOT CORRECT?	One way to deal with rapidly changing dimensions is by splitting the information into stable and rapidly changing information.  The latter can then be put into a separate mini-dimension table with a new surrogate key.  The connection can then be made by using the fact table or by introducing a new table connecting both.	incorrect	An outrigger table can be defined to store a set of attribute types of a dimension table which are uncorrelated, high in cardinality and updated simultaneously.	correct	For slowly changing dimensions, surrogate keys can be handy to store the historical information by duplicating a record and adding, e.g., Start_Date, End_Date and Current_Flag attribute types.	incorrect	Junk dimensions can be defined to efficiently accommodate low cardinality attribute types such as flags or indicators.	incorrect	
MC	Which statement is NOT CORRECT?	At the strategic level, decisions are made by senior management with long term implications (e.g., 1, 2, 5 years or more)	incorrect	At the tactical level, decisions are made by middle management with a medium-term (e.g. a month, a quarter, a year) focus.	incorrect	A data warehouse provides a centralized, consolidated data platform by integrating data from different sources and in different formats.  As such, it provides a separate and dedicated environment for operational decision making.	correct	At the operational level, day to day business decisions are made, typically in real-time or with a short time frame.	incorrect	
MC	Which statement is NOT CORRECT?	A snowflake schema normalizes the fact table of a star schema.	correct	A factless fact table is a fact table which only contains foreign keys and no measurement data.	incorrect	A fact constellation schema has more than one fact table which can share dimension tables.	incorrect	Surrogate keys essentially buffer the data warehouse from the operational environment by making it immune to any operational changes.	incorrect	
MC	Which statement is CORRECT?	A data lake is less agile compared to a data warehouse which has no structure.	incorrect	In terms of data manipulation, a data warehouse focusses on Delete statements.	incorrect	A snowflake schema normalizes the dimension tables such that report generation may go faster because there are less joins needed.	incorrect	In a fact constellation schema, more than one fact table is used.	correct	
MC	Which statement is NOT CORRECT?	A snowflake schema normalizes the fact table of a star schema.	correct	Surrogate keys essentially buffer the data warehouse from the operational environment by making it immune to any operational changes.	incorrect	A factless fact table is a fact table which only contains foreign keys and no measurement data.	incorrect	A fact constellation schema has more than one fact table which can share dimension tables.	incorrect