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如果不存在重复,则单行不能更新成多数据。
原标题:mysql cannot update one row to multi data when no duplicates exists
  • 时间:2023-12-15 02:41:08
  •  标签:
  • mysql

I m 试图通过询问更新我的表格。

UPDATE(
    tmp_a as a
    inner join 
    tmp_b as b
    on a.id=b.id)
set a.name=b.name,
    a.code=b.code;

这一回报无法更新一行,以弥补多数据错误。

然后,我尝试了以下提问:

create temporary table tmp_c(
    select a.id as id_a,a.name as name_a,a.code as code_a,
        b.id as id_b,b.name as name_b,b.code as code_b
    from(
    tmp_a as a
    inner join 
    tmp_b as b
    on a.id=b.id
    )
);

UPDATE tmp_c
set name_a=name_b
    code_a=code_b
;

我的理解是,在数据集中实际上不存在任何一行与多数据关系的问题。

那么,为什么在这里无法将一行更新到多数据错误,以及如何解决这个问题?

问题回答

我并不认为,我的SQL支持你的更新。 仅使用标准更新就加入:

UPDATE tmp_a a
INNER JOIN tmp_b b
    ON a.id = b.id
SET a.name = b.name,
    a.code = b.code;




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