How does the query optimizer in Oracle work, what does it consider, and to which class does it belong?
Middle
280
Data Engineer
671
0
What is the purpose of slicing data into blocks in HDFS?
Middle
264
How did you work with Impala?
Middle
241
How does HDFS differ from regular distributed file systems?
Middle
226
How does MapReduce work, specifically the Reduce stage?
Middle
212
What is YARN and why is it needed?
Middle
205
How have you worked with CI/CD?
Middle
200
How did you load data from S3 into Greenplum?
Middle
198
What is shuffle in Spark and why is it important to minimize it?
Middle
190
How to view the execution plan of a query in Oracle? How does EXPLAIN PLAN differ from EXPLAIN ANALYZE?
Middle
185
Tell about your experience using PL/SQL procedures in your work.
Middle
181
What is broadcast join in Spark?
Middle
177
Have you had experience optimizing Spark tasks? Can you give a specific example?
Middle
176
Have you ever worked with Oracle packages?
Middle
174
Have you worked with incremental and full loads? How did you deal with duplicates?
Middle
173
How is a file from HDFS, for example Parquet, read — entirely or in blocks?
Middle
167
What is the difference between RANK and DENSE_RANK?
Middle
167
What is the advantage of columnar storage over row-based storage?
Middle
167
What is Hive and how does it differ from traditional relational databases?
Middle
166
Tell about partitioning in Oracle: why it is used and what types exist?
Middle
162