本篇文章主要介绍了"select update case when"，主要涉及到方面的内容，对于其他数据库感兴趣的同学可以参考一下：
mysql case whenUPDATE tb_test
set name =
(
CASE
WHEN id = 1
...
mysql case when
UPDATE tb_test
set name =
(
CASE
WHEN id = 1
THEN (select * from (select DISTINCT name from tb_test where id = 2)t)
WHEN id = 2
THEN (select * from (select DISTINCT name from tb_test where id = 1)y)
END
);
UPDATE tb_test
set name =
(CASE
WHEN id = 1 THEN (select sub_query1.new_name from (select DISTINCT name as new_name from tb_test where id = 2 limit 1) as sub_query1 )
WHEN id = 2 THEN (select sub_query2.new_name from (select DISTINCT name as new_name from tb_test where id = 1 limit 1) as sub_query2)
END);
以上就介绍了select update case when，包括了方面的内容，希望对其他数据库有兴趣的朋友有所帮助。
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