Find duplicates in Postgres table and remove them

 To find all duplicates in table:

SELECT
    name,
    COUNT( name )
FROM
    client
GROUP BY
    name
HAVING
    COUNT( name )> 1
ORDER BY
    name;
To remove one: 
DELETE
FROM
    client a
        USING client b
WHERE
    a.id < b.id
    AND a.name = b.name;

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