check a column for duplicates postgresql code example

Example 1: postgres select duplicate columns

select Column1, Column2, count(*)
from yourTable
group by Column1, Column2
HAVING count(*) > 1

Example 2: postgresql remove duplicate rows 2 columns

DELETE FROM sf_table
WHERE id IN
    (SELECT id
    FROM 
        (SELECT id,
         ROW_NUMBER() OVER( PARTITION BY tosp, icd
        ORDER BY  id ) AS row_num
        FROM sf_table ) t
        WHERE t.row_num > 1 );