Which of the following database schemas features normalized dimension tables?
Correct Answer:
B
The correct answer is B. Snowflake.
A snowflake schema is a type of database schema that features normalized dimension tables. A database schema is a way of organizing and structuring the data in a database. A dimension table is a table that contains descriptive attributes or characteristics of the data, such as product name, category, color, etc. A normalized table is a table that follows the rules of normalization, which is a process of reducing data redundancy and improving data integrity by organizing the data into smaller and simpler tables12
A snowflake schema is a variation of the star schema, which is another type of database
schema that features denormalized dimension tables. A denormalized table is a table that does not follow the rules of normalization, and may contain redundant or duplicated data. A star schema consists of a central fact table that contains quantitative measures or facts, such as sales amount, order quantity, etc., and several dimension tables that are directly connected to the fact table. A snowflake schema differs from a star schema in that the dimension tables are further split into sub-dimension tables, creating a snowflake-like shape13
A snowflake schema has some advantages and disadvantages over a star schema. Some advantages are:
✑ It reduces the storage space required for the dimension tables, as it eliminates the
redundant data.
✑ It improves the data quality and consistency, as it avoids the update anomalies that may occur in denormalized tables.
✑ It allows more detailed analysis and queries, as it provides more levels of dimensions.
Some disadvantages are:
✑ It increases the complexity and number of joins required to retrieve the data from multiple tables, which may affect the query performance and speed.
✑ It reduces the readability and simplicity of the schema, as it has more tables and relationships to understand.
✑ It may require more maintenance and administration, as it has more tables to manage and update13
A financial institution is reporting on sales performance to a company at the account level. Due to the sensitive nature of the government the does il with, some account information is not shown. Which of the following fields should be masked?
Correct Answer:
D
Customer name is the field that should be masked, because it contains sensitive information that could identify the government accounts that the financial institution deals with. Masking is a technique that replaces or obscures sensitive data with dummy or random data, such as asterisks or hashes. Masking can help protect the privacy and security of the data, while still allowing for some analysis and reporting. Therefore, the correct answer is D. References: [Data Masking | Definition, Techniques & Examples - Talend], [Data masking - Wikipedia]
Which of the following would a data analyst look for first if 100% participation is needed on survey results?
Correct Answer:
A
Missing data is a type of data quality issue that occurs when some values in a data set are
not recorded or available. Missing data can affect the validity and reliability of survey results, especially if the missing values are not random or ignorable. Missing data can also reduce the sample size and the statistical power of the analysis12
If 100% participation is needed on survey results, a data analyst would look for missing data first, because missing data would indicate that some participants did not complete or submit the survey, or that some responses were not recorded or transmitted correctly. A data analyst would need to identify the causes and patterns of missing data, and apply appropriate methods to handle or prevent missing data, such as imputation, deletion, weighting, or follow-up12
An analyst collected data that includes primary account numbers, expiration dates, and service codes. Which of the following data governance classifications is used to describe this data?
Correct Answer:
B
An analyst is creating a resource to improve users' experience when they select specific records based on particular dates. Which of the following should the analyst use to create a resource that best meets user needs?
Correct Answer:
B
A drop-down menu is a graphical user interface element that allows users to select one option from a list of options that are hidden until the user clicks on the menu. A drop-down menu can be used to create a resource that best meets user needs when they select specific records based on particular dates, because:
✑ A drop-down menu can provide a predefined list of dates or date ranges that are relevant and valid for the records, such as today, yesterday, last week, last month, custom range, etc. This can help users to avoid typing errors or invalid dates in a text field, and to save time and effort in entering the dates.
✑ A drop-down menu can also provide a calendar or a date picker that allows users
to select a specific date or a range of dates from a graphical representation of a calendar. This can help users to visualize and compare the dates, and to easily adjust or modify their selection.
✑ A drop-down menu can improve the user experience by making the interface more
compact and organized, as it only shows one option at a time and hides the rest of the options until the user clicks on the menu. This can help users to focus on their selection and to avoid clutter and distraction.
