Find rows that have the same value on a column in MySQL

This query will give you a list of email addresses and how many times they're used, with the most used addresses first.

SELECT email,
       count(*) AS c
FROM TABLE
GROUP BY email
HAVING c > 1
ORDER BY c DESC

If you want the full rows:

select * from table where email in (
    select email from table
    group by email having count(*) > 1
)

select email from mytable group by email having count(*) >1

Here is query to find email's which are used for more then one login_id:

SELECT email
FROM table
GROUP BY email
HAVING count(*) > 1

You'll need second (of nested) query to get list of login_id by email.

First part of accepted answer does not work for MSSQL.
This worked for me:

select email, COUNT(*) as C from table 
group by email having COUNT(*) >1 order by C desc

use this if your email column contains empty values

 select * from table where email in (
    select email from table group by email having count(*) > 1 and email != ''
    )

Related