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Real questions from top companies in SQL · hard

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All Categories Behavioral Spark/Big Data SQL Python/Coding System Design/Architecture Cloud/Tools General/Othereasy medium hard

What is a Common Table Expression (CTE), and when would you use it?

SQLhardbigqueryoptimizationsnowflake0.4 min read

AccentureCognizantEPAMYash Technologies

What is the difference between a primary key and a unique key?

SQLhardsparksql0.4 min read

AccentureCognizantEPAMYash Technologies

Explain Fact and Dimension Tables with examples.

SQLhardjoin0.6 min read

DatameticaDeloitteIncedo

Joins and window functions - INNER, LEFT, RIGHT, FULL OUTER, ROW_NUMBER(), RANK(), DENSE_RANK()

SQLhardjoinpartitionwindow0.7 min read

FordKPMGNihilent

Difference Between Internal and External Tables in BigQuery

SQLhardbigqueryoptimizationpartition0.6 min read

EYIncedoTech Mahindra

How do you optimize a long-running SQL query?

SQLhardjoinoptimizationpartition0.6 min read

AareteDunnhumbyIncedo

7

Cloud Architecture - explain

SQLhard

8

Consolidate hotel reviews and create a dashboard. Design a data model for the reviews.

SQLhard

9

Create Spark Session, read CSV, join, and write as table. Provide example code.

SQLhard

10

Data Warehouse Design from scratch

SQLhard

11

Describe a challenging project where you optimized a complex ETL process.

SQLhard

12

Describe a recent project where you used AWS services extensively. What was your role, and what challenges did you face?

SQLhard

13

Describe a scenario where you used Databricks for real-time data processing.

SQLhard

14

Describe a situation where you had to redesign a data model to meet changing business needs

SQLhard

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