Data Warehousing Interview Questions

 
1.
What is Meta data?
2.
Briefly state different between data ware house & data mart?
3.
What is galaxy schema?
4.
Suppose you are filtering the rows using a filter transformation only the rows meet the condition pass to the target. Tell me where the rows will go that does not meet the condition.
5.
After we create a SCD table, can we use that particular Dimension as a dimension table for Star Schema?
6.
What is Core Dimension?
7.
How much data hold in one universe.
8.
Can any one explain about Core Dimension, Balanced Dimension, and Dirty Dimension?
9.
Can any one explain the Hierarchies level Data warehousing.
10.
What is data cleaning? How can we do that?
11.
What is dimension modeling?
12.
Where the cache files stored?
13.
How can you import tables from a database?
14.
What is drilling across?
15.
How Many different schemas or DW Models can be used in Siebel Analytics. I know Only STAR and SNOW FLAKE and any other model that can be used?
16.
What is an error log table in Informatica occurs and how to maintain it in mapping?
17.
What is loop in Data warehousing?
18.
How many clustered indexes can u create for a table in DWH? In case of truncate and delete command what happens to table, which has unique id.
19.
What is hybrid slowly changing dimension?
20.
Can a dimension table contain numeric values?
21.
How do you create Surrogate Key using Ab Initio?
22.
What is the difference between star and snowflake schemas?
23.
What is a CUBE in data warehousing concept?
24.
What is the difference between Snowflake and Star Schema? What are situations where Snowflake Schema is better than Star Schema when the opposite is true?
25.
What is ER Diagram?
26.
What is degenerate dimension table?
27.
What is VLDB?
28.
What is Dimensional Modeling?
29.
What are the various ETL tools in the Market?
30.
What are the possible data marts in Retail sales?
31.
What is meant by metadata in context of a Data warehouse and how it is important?
32.
What is a linked cube?
33.
What is surrogate key? Where we use it? Explain with examples.
34.
What are the data types present in BO? What happens if we implement view in the designer n report?
35.
What are data validation strategies for data mart validation after loading process?
36.
What is Data warehousing Hierarchy?
37.
What is BUS Schema?
38.
What are the methodologies of Data Warehousing?
39.
What is conformed fact?
40.
What is Difference between E-R Modeling and Dimensional Modeling?
41.
Why fact table is in normal form?
42.
What is junk dimension? What is the difference between junk dimension and degenerated dimension?
43.
What is the main difference between Inmon and Kimball philosophies of data warehousing?
44.
What is the difference between view and materialized view?
45.
What is the advantages data mining over traditional approaches?