Understand Delta Optimization Techniques, Such as Deletion Vectors and Liquid Clustering. DATA-ENGINEER-PROFESSIONAL Practice Questions (Page 6)

Questions 26–29

1. 26foundation · easy

   What is a primary performance benefit of liquid clustering?

   • AIt eliminates the need for caching
   • BIt reduces the number of files in the table
   • CIt improves data skipping, reducing the amount of data scanned for queries
   • DIt automatically indexes all columns in the table
   Reveal Solution Discussion Select an answer first
2. 27expert · hard

   A company has a Delta table that is partitioned by `date` and has frequent updates to the `status` column. Queries often filter on `status` and `date`. They are considering liquid clustering to improve query performance. What is a potential trade-off they should consider?

   • ALiquid clustering may increase write amplification because data may need to be reorganized during writes.
   • BLiquid clustering will reduce the number of files in the table.
   • CLiquid clustering will automatically delete old data.
   • DLiquid clustering will eliminate the need for partitioning.
   Reveal Solution Discussion Select an answer first
4. 28foundation · easy

   When is it most appropriate to use deletion vectors instead of a full file rewrite for deletes?

   • AWhen the table is used exclusively for append-only workloads
   • BWhen the table has a very high read-to-write ratio
   • CWhen deleting a small number of rows from a large table
   • DWhen deleting a large percentage of rows from a table
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5. 29foundation · easy

   What is a limitation of liquid clustering?

   • AIt can increase write overhead because data must be organized during writes
   • BIt only works with small tables
   • CIt prevents the use of deletion vectors
   • DIt requires the table to be partitioned
   Reveal Solution Discussion Select an answer first