Discuss differences between ROW_NUMBER(), RANK(), and DENSE_RANK(), and provide examples from your projects.
SQLmedium
2
Describe a time when you had to optimize a slow SQL query. What steps did you take?
SQLmedium
3
Explain the order in which SQL clauses are executed.
SQLmedium
4
How do you find duplicates in a table based on one or two columns?
SQLmedium
5
Two tables: Table 1 has 8 records, Table 2 has 2 records, common column id. How many records would result with Inner Join, Left Join, Right Join, Full Outer Join?
SQLmedium
6
Why is HAVING clause used only after GROUP BY?
SQLmedium
7
Write a query to retain only the latest record and delete others in case of duplicates.
SQLmedium
8
Write a query to select the latest record based on a time_of_insertion column.
SQLmedium
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