Practice Free PCAD-31-02 Exam Online Questions
What distinguishes structured data from unstructured data in the context of data modeling and storage?
- A . Structured data cannot be stored in databases
- B . Structured data follows a consistent schema or format
- C . Unstructured data contains only numeric values
- D . Unstructured data cannot be stored or analyzed
Which techniques are commonly used to manage type conversion between SQL and Python when importing database values? (choose two)
- A . Using a mapping function to convert SQL types into Python objects
- B . Ignoring data types and treating everything as strings
- C . Defining column types in Python using sqlite3.register_converter()
- D . Automatically casting Python variables to SQL column types without validation
Which tasks are commonly part of the data pre-processing phase? (Choose two)
- A . Encoding categorical variables
- B . Creating histograms for presentations
- C . Normalizing feature values
- D . Formatting plot titles for dashboards
Which conditions typically necessitate data normalization or scaling before analysis? (Choose two)
- A . Features with different units and scales
- B . Presence of duplicate data
- C . Distance-based modeling algorithms
- D . Boolean feature encoding
When creating a line chart with Matplotlib, which function is most appropriate to add a text label at a specific data point?
- A . plt.legend()
- B . plt.annotate()
- C . plt.xlabel()
- D . plt.title()
What does the standard deviation of a dataset represent in the context of statistical analysis?
- A . The sum of all values in the dataset
- B . The most frequently occurring value
- C . The average squared distance from the mean
- D . The number of outliers in the dataset
Which Python construct allows you to iterate over a list of dictionary values and apply conditional logic to accumulate numerical values that meet a certain threshold?
- A . for loop with if condition
- B . while loop with try block
- C . lambda expression with reduce
- D . filter() function with map
Which practices are considered part of professional Python scripting standards? (Choose two)
- A . Including in-line comments and docstrings
- B . Avoiding error handling to keep code clean
- C . Using consistent indentation and naming conventions
- D . Avoiding use of modules and libraries
What is the correct sequence to connect to a database and execute a query using the sqlite3 module in Python?
- A . Connect → Execute → Commit → Close
- B . Execute → Connect → Commit → Close
- C . Commit → Connect → Execute → Close
- D . Connect → Commit → Execute → Close
What is the correct SQL statement to permanently remove a table named customers from a database?
- A . REMOVE TABLE customers;
- B . DROP TABLE customers;
- C . DELETE TABLE customers;
- D . TRUNCATE TABLE customers;