Mysql 选择不同

Mysql select distinct(Mysql 选择不同)

问题描述

我正在尝试选择 mysql 表中的重复行，它对我来说工作正常，但问题是它不允许我选择该查询中的所有字段，只是让我选择我用作不同的字段名称，让我编写查询以更好地理解

I am trying to select of the duplicate rows in mysql table it's working fine for me but the problem is that it is not letting me select all the fields in that query , just letting me select the field name i used as distinct , lemme write the query for better understading

mysql_query("SELECT DISTINCT ticket_id FROM temp_tickets ORDER BY ticket_id")

mysql_query("SELECT * , DISTINCT ticket_id FROM temp_tickets ORDER BY ticket_id")

第一个工作正常

现在当我尝试选择所有字段时，我最终遇到了错误

now when i am trying to select all fields i am ending up with errors

我正在尝试选择最新的重复项，比如说，ticket_id 127 在行 id 7,8,9 上出现了 3 次，所以我想用最新的条目选择一次，在这种情况下为 9，这适用于所有其余的ticket_id

i am trying to select the latest of the duplicates let say ticket_id 127 is 3 times on row id 7,8,9 so i want to select it once with the latest entry that would be 9 in this case and this applies on all the rest of the ticket_id's

任何想法谢谢

推荐答案

您在寻找 "SELECT * FROM temp_tickets GROUP BY ticket_id ORDER BY ticket_id 吗?

更新

SELECT t.* 
FROM 
(SELECT ticket_id, MAX(id) as id FROM temp_tickets GROUP BY ticket_id) a  
INNER JOIN temp_tickets t ON (t.id = a.id)

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