prepare data for exploration weekly challenge 3 answers
1. Primary and foreign keys are two connected identifiers within separate tables. These tables exist in what kind of database?
- Metadata
- Primary
- Relational
- Normalized
2. When working with data from an external source, what can metadata help data analysts do? Select all that apply.
- Ensure data is clean and reliable
- Combine data from more than one source
- Understand the contents of a database
- Choose which analyses to run
3.Think about data as a student at a high school. In this metaphor, which of the following are examples of metadata? Select all that apply.
- Student’s ID number
- Student’s enrollment date
- Classes the student is enrolled in
- Grades the student earns
4. Fill in the blank: Data _____ is the process of ensuring the formal management of a company’s data assets.
- aggregation
- integrity
- mapping
- governance
5. In what circumstance might a data analyst choose not to use external data in their analysis?
- The data represents diverse perspectives
- The data is too thorough
- The data is free for anyone to access
- The data cannot be confirmed to be reliable
6. A nonprofit maintains a list of how many laptops they provide to each school in the county. In the table, there is a column called number_of_laptops. A data analyst wants to determine which schools were given the fewest laptops. How should they sort the data to return these schools first?
- Sort alphabetically in ascending order
- Sort numerically in descending order
- Sort alphabetically in descending order
- Sort numerically in ascending order
7.When writing a query, it's necessary for the name of the dataset to be inside two backticks in order for the query to run properly.
- True
- False
8. You are working with a database table that contains customer data. The city column lists the city where each customer is located. You want to find out which customers are located in Berlin.
You write the SQL query below. Add a WHERE clause that will return only customers located in Berlin.
How many customers are located in Berlin?
- 9
- 12
- 2
- 7
Shuffle Q/A 1
9. Relational databases contain a series of tables connected to form relationships. Which two types of fields exist in two connected tables?
- Star and snowflake schemas
- Descriptive and structural metadata
- Internal and external data
- Primary and foreign keys
10. Data analysts use metadata for what tasks? Select all that apply.
- To combine data from more than one source
- To perform data analyses
- To interpret the contents of a database
- To evaluate the quality of data
