mysql - 从 mysql 中选择重复值并显示所有这些值

Question

我目前有以下 SQL 查询来提取所有重复值:

Select `Racetime`,`Trainer`
from tom_cards
where `Trainer` in (
  select `Trainer`
  FROM tom_cards
  GROUP BY `Racetime`,`Trainer`
  HAVING COUNT(*) > 1
)

我想要更多类似的东西

Select `Racetime`,`Trainer`
from tom_cards
where `Trainer` and `Racetime in (
  select `Trainer` and `Racetime`
  FROM tom_cards
  GROUP BY `Racetime`,`Trainer`
  HAVING COUNT(*) > 1
)

但这无效。表达相同内容的有效查询是什么？

Answer 1

你可以连接

Select Racetime,Trainer from tom_cards 
where concat(Racetime,Trainer) in 
    (select concat(Racetime,Trainer) FROM tom_cards 
         GROUP BY Racetime,Trainer 
           HAVING COUNT(*) > 1)