MariaDB 10.4

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create table db1_content (id int, alias varchar(20), title varchar(20))
insert into db1_content values
(1999, 'title1', 'Title 1'),
(2345, 'title2', 'Title 2'),
(1765, 'title2', 'Title 2'),
(2953, 'title3', 'Title 3'),
(856, 'title2', 'Title 2'),
(2200, 'title1', 'Title 1')
select * 
from db1_content
order by id


id
alias
title


856
title2
Title 2

1765
title2
Title 2

1999
title1
Title 1

2200
title1
Title 1

2345
title2
Title 2

2953
title3
Title 3


WITH rns AS (
  SELECT *, 
         ROW_NUMBER() OVER (PARTITION BY title ORDER BY id DESC) AS rn
  FROM db1_content
)
SELECT id, alias, title
FROM rns
WHERE rn > 1


id
alias
title


1999
title1
Title 1

1765
title2
Title 2

856
title2
Title 2


DELETE db1 FROM db1_content db1
JOIN (
  SELECT id, 
         ROW_NUMBER() OVER (PARTITION BY title ORDER BY id DESC) AS rn
  FROM db1_content
  ) dbr ON db1.id = dbr.id
WHERE dbr.rn > 1
SELECT *
FROM db1_content


id
alias
title


2345
title2
Title 2

2953
title3
Title 3

2200
title1
Title 1

id	alias	title
856	title2	Title 2
1765	title2	Title 2
1999	title1	Title 1
2200	title1	Title 1
2345	title2	Title 2
2953	title3	Title 3