Question
Two statements are given, followed by three conclusions
numbered I, II and III. Assuming the statements to be true, even if they seem to be at variance with commonly known facts, decide which of the conclusions logically follow(s) from the statements. Statements: Some numbers are digits. All digits are letters. Conclusions: I. Some letters are numbers. II. All letters are numbers. III. No letter is a number.Solution
Some numbers are digits (I) + All digits are letters (A) → Some numbers are letters (I) → Conversion → Some letters are numbers (I). Hence conclusion I follows but conclusion II and III do not follow.
A star schema in a data warehouse consists of:
Surrogate keys are used in data warehouses because:
Fact constellation schema is best described as:
Which of the following best describes a fact constellation schema in a data warehouse?
What does "drill-down" operation in OLAP do?
Which OLAP operation involves focusing on a subset of dimensions (e.g., region=‘Asia’)?
Metadata in data warehousing refers to:
Which SQL clause is used to summarize data?
In a star schema, what is the main advantage of using surrogate keys in fact tables?
Data cleansing is primarily concerned with:
