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# Time: O(n^2)

# Space: O(n)

#

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

#

# +----+---------+

# | Id | Email |

# +----+---------+

# | 1 | a@b.com |

# | 2 | c@d.com |

# | 3 | a@b.com |

# +----+---------+

# For example, your query should return the following for the above table:

#

# +---------+

# | Email |

# +---------+

# | a@b.com |

# +---------+

# Note: All emails are in lowercase.

#

# Write your MySQL query statement below

SELECT Email FROM Person GROUP BY Email HAVING COUNT(*) > 1