Design and Implement Scalable Data Models Using Delta Lake to Manage Large Datasets. DATA-ENGINEER-PROFESSIONAL Practice Questions (Page 1)

Questions 1–5

1. 1application · medium

   Two teams write to the same Delta Lake table using different Spark jobs. Team A updates recent records, and Team B appends new records. They notice that Team A's updates sometimes fail due to conflicts. What should they do to reduce conflicts?

   • AUse `OPTIMIZE` with `ZORDER BY` to reduce conflicts
   • BPartition the table by a column that separates the write patterns
   • CSet the isolation level to `Serializable`
   • DDisable Delta Lake transaction logs
   Reveal Solution Discussion Select an answer first
2. 2foundation · easy

   Which component of Delta Lake enables time travel by storing information about each table version?

   • AThe catalog
   • BThe data files
   • CThe transaction log
   • DThe checkpoint file
   Reveal Solution Discussion Select an answer first
4. 3application · medium

   A retail company stores daily sales transactions in a Delta Lake table. The table is partitioned by `date` and queried frequently with filters on `store_id` and `product_id`. Recently, query performance has degraded as the table grew. The team wants to improve performance without changing the partitioning scheme. Which action should they take?

   • ADisable data skipping statistics collection to reduce overhead
   • BIncrease the number of partitions by adding a partition column for `store_id`
   • CRun VACUUM to delete old files and reduce table size
   • DRun OPTIMIZE with ZORDER BY (store_id, product_id)
   Reveal Solution Discussion Select an answer first
5. 4application · medium

   A company has a Delta Lake table that stores sales data. The table is partitioned by `year` and `month`. Queries often filter on `product_id` and `region`. The team wants to improve query performance. What should they do?

   • ARun VACUUM to reduce the table size
   • BRun OPTIMIZE with ZORDER BY (product_id, region)
   • CDisable statistics collection for `product_id` and `region`
   • DAdd `product_id` as a partition column
   Reveal Solution Discussion Select an answer first
6. 5foundation · easy

   Which Delta Lake command is used to compact small files into larger ones as part of regular table maintenance?

   • AVACUUM
   • BALTER TABLE
   • CREORG TABLE
   • DOPTIMIZE
   Reveal Solution Discussion Select an answer first