Suppose we have a table named "stock_item" in which the column quantity has duplicate values, i.e. for the item names "notebook" and "pencil", the column "quantity" has duplicate values "40", as shown in the table.
mysql> Select * from stock_item; +------------+----------+ | item_name |quantity | +------------+----------+ | Calculator | 89 | | Notebooks | 40 | | Pencil | 40 | | Pens | 32 | | Shirts | 29 | | Shoes | 29 | | Trousers | 29 | +------------+----------+ 7 rows in set (0.00 sec)
Now, with the help of the following query using MySQL JOINS, we can find the duplicate values in the "Quantity" column along with the item name.
mysql> Select distinct g.item_name,g.quantity from stock_item g -> INNER JOIN Stock_item b ON g.quantity = b.quantity -> WHERE g.item_name<>b.item_name; +-----------+----------+ | item_name | quantity | +-----------+----------+ | Pencil | 40 | | Notebooks | 40 | | Shoes | 29 | | Trousers | 29 | | Shirts | 29 | +-----------+----------+ 5 rows in set (0.00 sec)
The above is the detailed content of How can we find the duplicate values available in a MySQL table using JOINS?. For more information, please follow other related articles on the PHP Chinese website!