Write a SQL query to find all duplicate emails in a table named Person.

Write a SQL query to find all numbers that appear at least three times consecutively.

Write a SQL query to rank scores. If there is a tie between two scores, both should have the same ranking. Note that after a tie, the next ranking number should be the next consecutive integer value. In other words, there should be no “holes” between ranks.

Write a SQL query to get the second highest salary from the Employee table.

The Integer class wraps a value of the primitive type int in an object. An object of type Integer contains a single field whose type is int.