Duplicate Results Sql Query. To find duplicates in multiple column values we can use the following query. DELETE FROM products WHERE rowid IN SELECT MAX sl FROM SELECT itemcode rowid sl FROM products WHERE itemcode IN SELECT itemcode FROM products GROUP BY itemcode HAVING COUNT itemcode1 GROUP BY itemcode.
WITH cte AS SELECT a b COUNT occurrences FROM t1 GROUP BY a b HAVING COUNT 1 SELECT t1id t1a t1b FROM t1 INNER JOIN cte ON ctea t1a AND cteb t1b ORDER BY t1a t1b. First let us see how the following SELECT query returns duplicate salary records. However when you use the SELECT statement to query a portion of the columns in a table you may get duplicates.
To remove duplicates from a result set you use the DISTINCT operator in the SELECT clause as follows.
This would produce the following result where the salary of 2000 is coming twice which is a duplicate record from the original table. Hi Aung Mon Chit Htwe In addtion to the above suggestion. SQL treats items of the IN list as a set ignoring the duplicates. SELECT username email COUNT FROM users GROUP BY username email HAVING COUNT 1.