Hello,
I run the SQL query below to delete duplicates from a table. The subquery is used to identify the duplicated rows (row_num is a BIGSERIAL column).
/** delete older copies of duplicates */
DELETE FROM table_with_duplicates AS T
WHERE row_num IN (
SELECT T1.row_num
FROM table_with_duplicates AS T1
JOIN table_with_duplicates AS T2
ON T1.column_1 = T2.column_1
AND T1.column_2 = T2.column_2
AND T1.column_3 = T2.column_3
AND T1.row_num < T2.row_num
);
Can anyone tell me how to rewrite that query to use the USING clause and hopefully remove the subquery?
The documentation mentions USING but there is no example and the only examples I found online are very trivial.
Thanks,
