MySQL Удалить дубликаты
DELETE c1 FROM tablename c1
INNER JOIN tablename c2
WHERE
c1.id > c2.id AND
c1.unique_field = c2.unique_field;
Matteoweb
DELETE c1 FROM tablename c1
INNER JOIN tablename c2
WHERE
c1.id > c2.id AND
c1.unique_field = c2.unique_field;DELETE c1 FROM contacts c1
INNER JOIN contacts c2
WHERE
c1.id > c2.id AND
c1.email = c2.email;DELETE FROM FriendsData WHERE fID
NOT IN ( SELECT fID FROM FriendsData
GROUP BY UserID, FriendsUserID, IsSpecial, CreatedBy)
DELETE c1 FROM addresslist c1
INNER JOIN addresslist c2
WHERE
c1.id > c2.id AND
c1.`city` = c2.`city` AND
c1.`province` = c2.`province` AND
c1.`pgiRegion` = c2.`pgiRegion`DELETE FROM NAMES
WHERE id NOT IN (SELECT *
FROM (SELECT MIN(n.id)
FROM NAMES n
GROUP BY n.name) x)DELETE `yellow_page_content`
from `yellow_page_content`
inner join (
select max(`id`) as lastId, `code`
from `yellow_page_content`
group by `code`
having count(*) > 1) duplic on duplic.code = yellow_page_content.code
where yellow_page_content.id < duplic.lastId;