Mysql更新查詢示例表

Question

我有1個表稱爲樣本，它有3列。

id customer default_address 

1  1   0 
2  1     0 

3  1   0 
4  1   0 
5  2   0 
6  2   0 
7  3   0 
8  3   0 
9  2   0 

10 2   0 

在這裏，我想通過集團客戶和更新第一默認地址應該是1和其餘全部爲0爲每一位客戶。如何做到這一點的MySQL查詢？ 感謝

Answer 1

UPDATE tb a 
     LEFT JOIN 
     (
      SELECT customer, MIN(id) id 
      FROM tb 
      GROUP BY customer 
     ) b ON a.customer = b.customer AND 
       a.ID = b.ID 
SET  a.default_address = b.ID IS NOT NULL 

• SQLFiddle Demo

Answer 2

UPDATE sample 
    LEFT JOIN 
    (SELECT MIN(id) id,customer 
    FROM sample 
    GROUP BY customer) t ON sample.customer=t.customer 
SET default_address="1" 
WHERE sample.id=t.id; 

這應該工作。

Answer 3

Update Table1 
INNER JOIN (Select Min(`id`) as MinID,`customer` 
From Table1 Group by `customer`) t2 
SET Table1.`default_address` = 1 
WHERE Table1.`id` = t2.MinID; 

SAMPLE FIDDLE