Count highest no of conversation between two clients

Question

I have a table called email with three columns say id, emailFrom, emailTo

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| id | emailFrom        | EmailT0                |
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| 1  | A                | B                      |
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| 2  | B                | A                      |
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| 3  | A                | B                      |
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| 4  | C                | A                      |
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| 5  | B                | C                      |
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| 6  | A                | C                      |
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| 7  | A                | B                      |
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now my question is , how to find out the highest conversation between two clients

i.e. A send mail to B and B send mail to A, it means they have conversation of count 2. now,
I want to find that which users have send most emails to each other

Answer 1

This will return the users that have sent most emails to each other:

SELECT
  LEAST(emailFrom, emailTo) email1,
  GREATEST(emailFrom, emailTo) email2,
  COUNT(*)
FROM
  yourtable
GROUP BY
  LEAST(emailFrom, emailTo),
  GREATEST(emailFrom, emailTo)
ORDER BY
  COUNT(*) DESC
LIMIT 1

Please see fiddle here.