What does the Catalyst optimizer do in Spark SQL?

In MapReduce, what happens during the Shuffle phase?

In SparkML, what is the difference between a Transformer and an Estimator?

Which SparkML component combines multiple feature columns into a single vector column?

Delta Lake stores data in the open [blank1] file format while adding a metadata layer for ACID transactions. [response_blank1]

Which of the following is a Spark transformation (lazy operation)?

In SparkML, a [blank1] chains together multiple transformers and estimators into a single workflow. [response_blank1]

What problem did the ‘Two-System Architecture’ (separate data lake and warehouse) create?

Suppose the government imposes a specific tax per unit on a good sold in a perfectly competitive market. Demand for the good is given by QD = 100 – 2 P and supply is given by QS = 4 P.   Where P is the price consumers pay. Assume the tax revenue is rebated lump-sum to consumers. Which of the following statements is most accurate regarding the welfare effects of the tax?

Mitosis produces cell that are _________ and meiosis produces cells that are ___________.