Mysql delete older duplicates

Mysql remove duplicates

DELETE c1 FROM tablename c1
INNER JOIN tablename c2 
WHERE
    c1.id > c2.id AND 
    c1.unique_field = c2.unique_field;

Mysql delete older duplicates

DELETE FROM CONTACTS
WHERE ID NOT IN
      (SELECT *
       FROM (SELECT max(ID)		
             FROM CONTACTS
             GROUP BY EMAIL) t);
 -- ⇓ Test it ⇓ (Fiddle source link)

Source: sqlfiddle.com

Mysql delete older duplicates

 delete test
   from test
  inner join (
     select max(id) as lastId, email
       from test
      group by email
     having count(*) > 1) duplic on duplic.email = test.email
  where test.id < duplic.lastId;

Source: stackoverflow.com

Mysql remove duplicates

DELETE t1 FROM contacts t1
INNER JOIN contacts t2 
WHERE 
    t1.id < t2.id AND 
    t1.email = t2.email;Code language: SQL (Structured Query Language) (sql)

-1

Source: mysqltutorial.org

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