如何使用Join更新select

Question

如何更新子查询中也存在的表？我需要分2个阶段吗？(创建一个临时表 - 将所选数据放入其中,然后更新最终表)

我正在尝试使用每个CTN的网络标签更新invoiceLine表.

最终结果将是:

• invoiceLine

  ctn       network
  1234      network1
  2345      network2
  3456      network1
  

我有以下表格:

• invoiceLine

  ctn       network
  1234      null
  2345      null
  3456      null
  

• 终奌站

  ctn       network
  1234      1
  2345      2
  3456      1
  

• 网络

  id        label
  1         network1
  2         network2
  

我可以运行一个选择,但我不知道如何使用连接更新:

update invoiceLine 
inner join terminal on terminal.ctn = invoiceLine.ctn 
set invoiceLine.network = 
(
  select network.label 
  from invoiceLine 
  inner join terminal on terminal.ctn = invoiceLine.ctn 
  inner join network on network.id = terminal.network
) 
where invoiceLine.ctn = terminal.ctn

但MySQL抛出一个

错误代码:1093.您无法在FROM子句中为更新指定目标表'invoiceLine'

Answer 1

UPDATE invoiceLine
    INNER JOIN terminal
        ON invoiceLine.ctn = terminal.ctn
    INNER JOIN network
        ON terminal.network = network.id
    SET invoiceLine.network = network.label

Answer 2

UPDATE invoiceLine SET network = (
    SELECT label FROM network WHERE id = (
        SELECT network FROM terminal WHERE terminal.ctn = invoiceLine.ctn
    )
)