Data Engineering Associate with Databricks Practice Exam

How can data retrieval be sped up using ZORDER functionality?

1. By compressing the data files

2. By colocating data based on specified fields

3. By encrypting the stored data

4. By aggregating data into smaller subsets

The correct answer is: By colocating data based on specified fields

ZORDER functionality significantly enhances data retrieval performance by colocating related data based on specified fields. This approach organizes data within the underlying storage in a way that ensures records that are frequently queried together are physically stored close to one another. As a result, when a query is executed, the system has to read fewer data blocks, leading to faster access times. This optimization is particularly useful for scenarios where queries involve filtering or aggregating data based on certain dimensions. By using ZORDER, the query engine can minimize the amount of data scanned, thus improving the performance of read operations and minimizing the latency of data retrieval. The other options do not directly relate to the core functionality of ZORDER. Compressing data files can reduce storage space but doesn't directly affect retrieval speed in the same manner. Encrypting stored data adds a layer of security but can potentially slow down read times due to the overhead of decryption. Aggregating data into smaller subsets might help with processing speed but doesn't specifically address the optimization of physical data layout as ZORDER does.