问题描述

我需要更新一个 SQLite 表.

I need to update a SQLite table.

表格如下:

ID   | Address            | CallNumber   |  RefID
-----+--------------------+-------------------------------------------
ef78 | library            | 2002/13      | 100002
no56 | Lit                | 0189         | 100003
rs90 | temp               |              | 100003

对于 Address = "Lit" 的每一列，都有一个 Address = 'temp' 的列具有相同的 RefID.现在我需要使用具有相同 RefID 的列中的值CallNumber"更新每个 Address = temp".

For every column with Address = "Lit" there is a column Address = 'temp' with the same RefID. Now I need to update each Address = "temp" with the value "CallNumber" from the column with the same RefID.

更新后的表格应如下所示:

The updated table should look like:

ID   | Address            | CallNumber   |  RefID
-----+--------------------+-------------------------------------------
ef78 | library            | 2002/13      | 100002
no56 | Lit                | 0189         | 100003
rs90 | 0189               |              | 100003

我试过了:

UPDATE Location
SET address = foo.callnumber
FROM (select RefID, CallNumber FROM Location) foo
WHERE foo.RefID=Location.RefID AND Location.Address = 'temp';

但我得到的只是来自"附近的语法错误.

But all I got is a syntax error near "from".

有什么线索吗?

推荐答案

UPDATE 命令 没有FROM 子句.

UPDATE commands do not have a FROM clause.

使用相关子查询:

UPDATE Location
SET Address = (SELECT CallNumber
               FROM Location L2
               WHERE L2.RefID = Location.RefID
                 AND L2.Address = 'Lit')
WHERE Address = 'temp'

这篇关于SQLite 更新查询 - 带有别名的子查询不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！