Which statement describes how data will be filtered?

A Delta Lake table representing metadata about content posts from users has the following schema:

user_id LONG, post_text STRING, post_id STRING, longitude FLOAT, latitude FLOAT, post_time TIMESTAMP, date DATE

This table is partitioned by the date column. A query is run with the following filter:

longitude < 20 & longitude > -20

Which statement describes how data will be filtered?
A . Statistics in the Delta Log will be used to identify partitions that might Include files in the filtered
range.
B . No file skipping will occur because the optimizer does not know the relationship between the partition column and the longitude.
C . The Delta Engine will use row-level statistics in the transaction log to identify the flies that meet the filter criteria.
D . Statistics in the Delta Log will be used to identify data files that might include records in the filtered range.
E . The Delta Engine will scan the parquet file footers to identify each row that meets the filter criteria.

View Answer

Answer: D

Explanation:

This is the correct answer because it describes how data will be filtered when a query is run with the following filter: longitude < 20 & longitude > -20. The query is run on a Delta Lake table that has the following schema: user_id LONG, post_text STRING, post_id STRING, longitude FLOAT, latitude FLOAT, post_time TIMESTAMP, date DATE. This table is partitioned by the date column. When a query is run on a partitioned Delta Lake table, Delta Lake uses statistics in the Delta Log to identify data files that might include records in the filtered range. The statistics include information such as min and max values for each column in each data file. By using these statistics, Delta Lake can skip reading data files that do not match the filter condition, which can improve query performance and reduce I/O costs.

Verified Reference: [Databricks Certified Data Engineer Professional], under “Delta Lake” section; Databricks Documentation, under “Data skipping” section.