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Answer: Z-Ordering is a method of sorting data that improves query performance by reducing the number of files that need to be scanned, without increasing storage costs or violating data governance policies.
The correct answer is A. Z-Ordering is a method of sorting data that groups together rows with similar values across multiple columns, resulting in a more efficient data layout. This optimization reduces the amount of data that needs to be scanned during queries, thereby improving performance. Importantly, it achieves this without increasing storage costs or compromising data governance policies, making it an ideal solution for the given scenario.
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In the context of optimizing query performance on Delta Lake tables, consider a scenario where a data engineer is tasked with improving the speed of analytical queries on a large dataset that is frequently queried by multiple departments within an organization. The dataset contains millions of rows and is partitioned by date. The engineer is considering implementing Z-Ordering to enhance query performance. Given the constraints of minimizing storage costs and ensuring compliance with data governance policies, which of the following best describes the benefit of Z-Ordering and its impact on query performance? Choose the single best option.
A
Z-Ordering is a method of sorting data that improves query performance by reducing the number of files that need to be scanned, without increasing storage costs or violating data governance policies.
B
Z-Ordering is a technique used to compress data files, resulting in smaller file sizes and faster query performance, but it may increase CPU usage during compression and decompression.
C
Z-Ordering is a method of partitioning data that allows for parallel processing of queries, improving overall query performance, but it requires additional storage for each partition.
D
Z-Ordering is a feature that enables real-time data processing and streaming, allowing for faster query results, but it necessitates continuous data ingestion and processing resources.