Question

In a data analysis workflow, an index is created on a column with very low cardinality (e.g., a 'gender' column). What is a potential consequence of this?

Q: Answer-In a data analysis workflow, an index is created on a column with very low cardinality (e.g., a 'gen...

For columns with very low cardinality few distinct values, an index might not be beneficial. The query optimizer might decide that a full table scan is more efficient than using the index, as the index would point to a large percentage of the rows anyway.