如果两列相等，MySQL查询删除行

Question

How to delete all rows from a mysql table if values of two columns are equal

Example Table

invoice_id| item_id | name  | invoiced_qty | received_qty
---------------------------------------------------------
|  1      |  1      | item1 |   3          |     2    
|  2      |  2      | item2 |   5          |     5   
|  3      |  1      | item3 |   4          |     3   
|  4      |  2      | item4 |   2          |     2   
|  5      |  1      | item5 |   5          |     5

After deleting table needs to retains

invoice_id| item_id | name  | invoiced_qty | received_qty
---------------------------------------------------------
|  1      |  1      | item1 |   3          |     2    
|  3      |  1      | item3 |   4          |     3   

The select query which i created is

SELECT * FROM table1 A 
INNER JOIN table1 B ON A.item_id = B.item_id 
AND A.invoice_id = B.invoice_id
AND A.invoiced_qty = B.received_qty

Thanks

Answer 1

Why not just SQL Fiddle :

DELETE FROM table1 
WHERE invoiced_qty = received_qty

Your edit does not change anything. He is the SQL Fiddle demonstrating your SELECT query. According to your sample data A.invoice_id will never equal B.invoice_id . So you will not get any results.

Answer 2

You could simply wrap your select statement and select values to be deleted by id, like this:

DELETE FROM table1 
WHERE item_id  IN (SELECT item_id FROM table1 A 
INNER JOIN table1 B ON A.item_id = B.item_id 
AND A.invoice_id = B.invoice_id
AND A.invoiced_qty = B.received_qty)

however you should accept answer by Linger as it is more straightforward solution, mine was to indicate that if you have something selected usually you can wrap and delete.

Answer 3

Try this :

DELETE FROM table1 A
INNER JOIN table1 B ON A.item_id = B.item_id 
WHERE A.invoiced_qty = B.received_qty