Data Engineer
NULL plus 5 — what will it be?
Is it possible to read data in parallel from a single Parquet file in Spark, or only with one core in one task?
What Python libraries have you worked with?
What are lazy operations in Spark and what are they used for?
AstonWhat is a CROSS JOIN and what is its result?
What is the difference between ACID and the CAP theorem?
ОстровокOn which fields did the data merging occur and how were duplicates eliminated in the view?
What types of partitions are there?
What do you know about spill in Spark?
ОстровокWhat physically happens during INSERT, UPDATE, and DELETE in Greenplum; why is disk space not freed after DELETE and how does DELETE differ from TRUNCATE?
How was the parallel extraction of a large table from PostgreSQL to Spark technically implemented in the [context] case?
How did you work with files when restarting the DAG after it failed, to avoid overwriting data in S3 with incomplete data?
How to distribute storefront data unevenly across three shards: 50% on the first and 25% on each of the remaining two? How to implement this?
Write SQL to add a running total of order sums by user and date.
What types of keys/distribution strategies exist in Greenplum?
How did you connect to OpenMetadata and what did you do with it?
Лига Цифровой ЭкономикиIs it possible to create and apply a decorator without the @ syntax?
Как работать с партициями через coalesce и repartition?
If the DAG schedule is @daily, what time does it actually run?
ОстровокAre you familiar with ReplicatedQueue? Have you worked with it?