Sigma Head Interview Questions and Answers

Rank, Dense Rank, and Row Number are window functions used in SQL to assign a rank to each row based on a specific criteria.

• Rank assigns a unique rank to each row based on the specified order.

• Dense Rank assigns a unique rank to each row without any gaps, even if there are ties.

• Row Number assigns a unique sequential integer to each row, without any regard to the order of the rows.