更新：您无法在FROM子句中指定目标表'表'进行更新

Question

我有两个针对oracle的查询。我需要修改它们的MySQL。 首先查询：

UPDATE tec_onoff_file a 
SET emailtype = 'MIGR' 
WHERE EXISTS 
    (SELECT 1 
     FROM tec_onoff_file 
     WHERE emailtype = 'MIGR' 
     AND a.acctnbr = acctnbr 
     AND a.magabbr = magcodes); 

我改成了

update tec_onoff_file t1 
join tec_onoff_file t2 
    on t2.emailtype='MIGR' 
    and t1.acctnbr=t2.acctnbr 
    and t1.magabbr=t2.magcodes 
    set t1.emailtype='MIGR'; 

和它的作品。 但是第二个查询是很难对我来说

update tec_onoff_file a 
set emailtype = 'REIN' 
where transtype = 'REIN' 
and curracctnbr not in (select curracctnbr from tec_onoff_file b 
    where emailtype ='RENW' 
    and a.curracctnbr=b.curracctnbr); 

可能有人有帮助？我试图改变它像第一个查询JOIN，但它失败了，我不知道该怎么做。

Answer 1

UPDATE tec_onoff_file a 
    LEFT 
    JOIN tec_onoff_file n 
    ON b.curracctnbr = a.curracctnbr 
    AND b.emailtype ='RENW' 
    SET emailtype = 'REIN' 
WHERE a.transtype = 'REIN' 
    AND b.transtype IS NULL;