liyupi / sql-mother

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自定义关卡-冒险者和金币 #27

Closed poorerdai closed 11 months ago

poorerdai commented 11 months ago

看答案中group_by adventurer_id,adventurer_name。但是adventurer_id已经是用户的唯一标识了,所以group_by adventurer_id应该就够了,没必要再加上adventurer_name了吧?

liyupi commented 11 months ago

如果你要查询 adventurer_id,adventurer_name 两个字段,那么 group by 也要包含这两个字段

poorerdai commented 11 months ago

如果是MySQL 8 sql_mode 默认开启了ONLY_FULL_GROUP_BY,查询的字段group by 需要包含,但是如果没有开启ONLY_FULL_GROUP_BY,只需要group by adventurer_id就可以了。