Question

我有一个mysql表proforma_invoice_items

-----------------------------------------
    id  |   qty |   total_invoice_qty   |
-----------------------------------------
    452 |   50  |   45                  |

现在，我想用total_invoice_qty增加10值，但不是qty值增加50

我试过下面的查询：

update proforma_invoice_items a set a.total_invoice_qty = a.total_invoice_qty+10 where a.id = 452 and a.total_invoice_qty < a.qty

结果是：

-----------------------------------------
    id  |   qty |   total_invoice_qty   |
-----------------------------------------
    452 |   50  |   55                  |

我的预期结果是最大qty值50，如

-----------------------------------------
    id  |   qty |   total_invoice_qty   |
-----------------------------------------
    452 |   50  |   50                  |

Answer 1

您可以使用LEAST()：

使用两个或多个参数，返回最小值（最小值）参数。

UPDATE proforma_invoice_items a
SET a.total_invoice_qty = LEAST(a.total_invoice_qty + 10, a.qty)
WHERE a.id = 452

Answer 2

UPDATE proforma_invoice_items 
SET total_invoice_qty  =  CASE WHEN total_invoice_qty  + 10 > qty THEN qty
                               ELSE  total_invoice_qty  + 10 END
WHERE id = 452

Answer 3

希望以下查询可以帮助您

update proforma_invoice_items a 
set a.total_invoice_qty = 
            a.total_invoice_qty + (Case WHEN a.qty - a.total_invoice_qty >= 0 THEN 10 ELSE a.qty - a.total_invoice_qty END)  where a.id = 452 and a.total_invoice_qty < a.qty

Answer 4

通用查询不能像WHERE id = 452那样进行硬编码，请尝试使用

UPDATE proforma_invoice_items  
SET total_invoice_qty  = CASE
   WHEN  (total_invoice_qty+10) < 50 THEN total_invoice_qty+10
   ELSE 50
END

Answer 5

update proforma_invoice_items a set a.total_invoice_qty = case when a.total_invoice_qty+10 < a.total_invoice_qty then a.total_invoice_qty+10 else a.total_invoice_qty end  where a.id = 452 and a.total_invoice_qty < a.qty

试试这个

增加数量但不多于主数量字段

5 个答案: