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All CategoriesBehavioralSpark/Big DataSQLPython/CodingSystem Design/ArchitectureCloud/ToolsGeneral/Othereasymediumhard
1

How would you handle data type changes for an existing column?

SQLmedium
2

How would you handle duplicate or corrupted data in a batch ETL job?

SQLmedium
3

How would you handle null values in a dataset, especially in a single column?

SQLeasy
4

How would you handle nulls in a SQL join? Provide examples using COALESCE.

SQLmedium
5

How would you identify duplicate records based on a composite key in SQL?

SQLmedium
6

How would you optimize a SQL query for better performance when working with large datasets?

SQLhard
7

How would you optimize a query fetching sales data across multiple countries with billions of rows?

SQLmedium
8

How would you optimize a query with multiple joins and subqueries?

SQLmedium

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