WorksheetsData warehousing
Total questions: 12
Worksheet time: 12mins
Which of the following statements is not correct?
OLTP Solutions are best used with business execution databases, whereas data warehouses are best suited for analytical purposes
Data warehouses handle a smaller number of in-house users compared to Transactional databases that can handle thousands of users at one time
Data warehouses contain only the current state of information, which makes historical queries impossible.
Data warehouses typically denormalize their data, prioritizing high-performance reads over writes
Process of analyzing the data in different dimensions or perspectives and summarizing into a useful information is called:
Data Warehousing
Data modeling
Data Analysis / Data Mining
None
Which option is not in Four-Step Dimensional Design Process?
Select the Business Process
Declare the grain
Identify the Dimensions
Identify the Customers
Tables that have been "grouped" to certain level of dimensions are called :
Fact tables
Dimension tables
Summary / Aggregate tables
None of the above
what option is not included in data warehouse modeling?
Fact tables and dimensions tables
Bottom-up drive approach
Star schemas and Multidimensional models (cube)
Normalization and denormalization
System generated unique, meaningless, and sequential numbers attached to data warehouse tables are called:
Source keys
Natural or business keys
Surrogate Keys
Hashing Keys
What are the ACID properties of database transactions?
Atomicity, Consistency, Isolation, Database
Atomicity, Consistency, Isolation, Durability
Atomicity, Consistency, Inconsistency, Durability
Automatically, Concurrency, Isolation, Durability
This refers to a database layer that stores raw data from source systems in an ELT data warehouse
Data Integration Layer
Access Layer
Staging Layer
Semantic Layer
It is a Star Schema which is further split to smaller dimension tables to avoid redundancies
Atomic Schema
Snowflake Schema
Composite Schema
Extension Schema
A type of Slowly Changing Dimension (SCD) that uses "Start_date" and "End_date" fields to keep history
Type 0: Retain Original
Type 1: Overwrite
Type 2: Add new row
Type 4: Add mini-dimension (History / Audit table)
Refers to splitting what is logically one large table into smaller physical pieces to improve query performance
Table Partitioning
Table Clustering
Table Indexing
Table compaction
Which is not a data warehouse best practice ?
Use Snowflake schema to reduce redundancies
Maintain a staging layer to store raw data from source
Enforce idempotency in your data pipelines
Partition large fact tables
