Real questions from top companies in SQL
Write an SQL query to find duplicate emails in a users table.
Triggers in ADF, especially tumbling window triggers.
What is a CTE (Common Table Expression)? What are its uses?
What is a window function? Explain with an example.
What is the difference between OLTP and OLAP?
Write a SQL query to find top 3 earners in each department.
Write a query to find the top three highest-paid employees in each department using window functions.
Write complex SQL queries involving multiple joins, subqueries, and data aggregation logic.
Add Row Numbers using window function in PySpark
Add a column to the Employees table that shows the name of the employee with the next higher employee_id.
Add a new column with manager names for each employee using a self-join.
Add a new column with the average salary by department.
Advanced SQL with CTEs and Conditional Joins
Aggregate surface areas and calculate cumulative surface area using the LAG function.
Analyze the output of various joins (LEFT, RIGHT, INNER, CROSS, FULL OUTER) on the given tables.
Are you comfortable with the variable pay structure, and what are your expectations for the base salary?
Building ETL pipelines to capture changes when new records are inserted into source tables?
CSV Without Column Names/Schema - how to read
Calculate the cumulative transaction amount for each month using a transaction table.
Can CASE statements be used in an UPDATE query?
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