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

Select where duplicate mysql

SELECT 
    col1, COUNT(col1),
    col2, COUNT(col2)
FROM
    table_name
GROUP BY 
    col1, 
    col2
HAVING 
       (COUNT(col1) > 1) AND 
       (COUNT(col2) > 1);

Source: mysqltutorial.org

How to delete all duplicate items in mysql

DELETE FROM FriendsData WHERE fID 
       NOT IN ( SELECT fID FROM FriendsData 
                   GROUP BY UserID, FriendsUserID, IsSpecial, CreatedBy)

Mysql delete duplicate rows but keep one

DELETE c1 FROM contacts c1
INNER JOIN contacts c2 
WHERE
    c1.id > c2.id AND 
    c1.email = c2.email;

Source: mysqltutorial.org

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

Similar codes

1 vote219 views3 answers
Postgresql connect to database
SQL
0 vote167 views1 answer
Mariadb list tables
SQL
4 votes200 views4 answers
Start mysql
SQL
0 vote200 views1 answer
T-sql conditional order by multiple columns
SQL
0 vote215 views1 answer
Add sqlcmd to path linux
SQL
0 vote208 views1 answer
Setval in postgres
SQL
13 votes218 views4 answers
Command line mysql import
SQL
3 votes209 views1 answer
Show index table
SQL
0 vote211 views1 answer
Move table to a different schema
SQL
0 vote266 views1 answer
Using distinct and count together in sql
SQL