Exam Databricks-Certified-Professional-Data-Engineer Topic 1 Question 115 Discussion

Explanation
This is the correct answer because it is true of Delta Lake and the Lakehouse. Delta Lake uses Parquet as the underlying storage format for data files. Parquet is a columnar format that compresses data by column rather than by row. This means that Parquet can achieve high compression ratios for columns that have low cardinality or high repetition of values, such as integers, booleans, or dates. However, for columns that have high cardinality or low repetition of values, such as strings, Parquet cannot compress data very well.
Therefore, strings will only be compressed when a character is repeated multiple times within a row. Verified References:[Databricks Certified Data Engineer Professional], under "Delta Lake" section; Databricks Documentation, under "Delta Lake core features - Schema enforcement and evolution" section.