Question

我有一张包含这些值的表格：

Name       |  id
----------------
Blue guy   |  20
Green girl |  10

id列是唯一值。我想要的是将blue guy id更新为10，并在同一查询中我想将绿色女孩ID更新为20.我当前的SQL查询是：

UPDATE colorpeople SET id = 20
WHERE name = 'Blue guy';

我可以在哪里指定更新绿色女孩？

Answer 1

试试这个：

UPDATE colorpeople 
SET id = (case 
           when name = 'Blue guy' then 10   
           when name = 'Green girl' then 20 
           else id = id 
           end)

Answer 2

请尝试以下脚本：

ALTER TABLE colorpeople DROP CONSTRAINT PK_colorpeople

UPDATE colorpeople SET ID = 10 WHERE Name = 'Blue guy'
UPDATE colorpeople SET ID = 20 WHERE Name = 'Green girl'

ALTER TABLE colorpeople ADD CONSTRAINT PK_colorpeople PRIMARY KEY /* CLUSTERED */ (ID)

Answer 3

你应该尝试这样的事情：

INSERT INTO colorpeople id VALUES 10, 20
ON DUPLICATE KEY UPDATE id=VALUES(id);

Answer 4

执行此操作的最佳方法是使用WHERE子句：

UPDATE colorpeople 
    SET id = (case when name = 'Blue guy' then 10
                   when name = 'Green girl' then 20
              end)
    WHERE name in ('Blue guy', 'Green girl');

Answer 5

如果您想更新已存在的唯一键

UPDATE colorpeople SET id = -20 WHERE naam = 'Blue guy';
UPDATE colorpeople SET id = -10 WHERE naam = 'Green girl';
UPDATE colorpeople SET id = -id WHERE naam in ('Blue guy', 'Green girl');

如何使用sql更新列两次

5 个答案: