Databricks Certified Associate Developer for Apache Spark Practice Mode

Community Discussion

Written by other learners. Comments can disagree with the marked answer — check the official documentation when in doubt.

• Chose A0

  - df.cache() is shorthand for df.persist(StorageLevel.MEMORY_AND_DISK). It marks the DataFrame to be cached upon the next action (lazy). Used to reuse expensive intermediate results across actions. collect returns data to the driver; cache keeps it distributed.