Mysql 一夫一妻的关系。如何提出请求?

Mysql 一夫一妻的关系。如何提出请求?,mysql,sql,Mysql,Sql,你好。我是SQL方面的noob,所以如果您帮助我编写一个SQL请求,从tennisset表中获取FINALSCORE字段,我将不胜感激,该表与tennismatch相关,其中id=1 谢谢。尝试以下查询: select FINALSCORE from tennismatch join tennismatch_tennisset on tennismatch.ID = tennismatch_tennisset.TennisMatch_ID and tennismatch.ID = 1 join

你好。我是SQL方面的noob,所以如果您帮助我编写一个SQL请求,从tennisset表中获取FINALSCORE字段,我将不胜感激,该表与tennismatch相关,其中id=1

谢谢。

尝试以下查询:

select FINALSCORE from
tennismatch join
tennismatch_tennisset on tennismatch.ID = tennismatch_tennisset.TennisMatch_ID and tennismatch.ID = 1 join 
tennisset on tennismatch_tennisset.mapOfSets_ID = tennisset.ID
要从表“tennismatch”中删除记录,请首先从子表“tennismatch_tennisset”中删除该记录

试着这样做:

delete from tennismatch_tennisset where TennisMatch_ID =1 
delete from tennismatch where id=1
请尝试以下查询:

select FINALSCORE from
tennismatch join
tennismatch_tennisset on tennismatch.ID = tennismatch_tennisset.TennisMatch_ID and tennismatch.ID = 1 join 
tennisset on tennismatch_tennisset.mapOfSets_ID = tennisset.ID
要从表“tennismatch”中删除记录,请首先从子表“tennismatch_tennisset”中删除该记录

试着这样做:

delete from tennismatch_tennisset where TennisMatch_ID =1 
delete from tennismatch where id=1

您需要在表之间使用联接。在您的情况下,它必须通过tenismatch_tenisset完成,这是两者之间的绑定表

select finalscore from tennismatch m 
join tenismatch_tennisset ms 
    on m.id = ms.tennismatch_id 
join tennisset s 
    on ms.mapofsets_id = s.id 
where m.id = 1

您需要在表之间使用联接。在您的情况下,它必须通过tenismatch_tenisset完成,这是两者之间的绑定表

select finalscore from tennismatch m 
join tenismatch_tennisset ms 
    on m.id = ms.tennismatch_id 
join tennisset s 
    on ms.mapofsets_id = s.id 
where m.id = 1

如果其他人为您编写查询,您不会有任何进步。我相信我会的,只是需要了解如何做。迈出第一步。你应该从开始,然后继续,如果你仍然被卡住,那么现在就带着你的代码回来。还请阅读如何准备简单地联接tennismatch表和tennisset表,我需要tennismatchID在tennisset表中。这里我处理的是OneToMany关系,对自动生成的表tennismatch_tennisset感到困惑。这可能是通过您的查询
select*from tennismatch m join tenismatch_tennisset ms on m.id=ms.tennismatch_id join tennisset s on m.mapofsets_id=s.id其中m.id=1
如果有人else为您编写查询。我相信我会的,只是需要了解如何执行。迈出第一步。你应该从开始,然后继续,如果你仍然被卡住,那么现在就带着你的代码回来。还请阅读如何准备简单地联接tennismatch表和tennisset表,我需要tennismatchID在tennisset表中。这里我处理的是一对一的关系,对自动生成的表tennismatch_tennisset感到困惑。这可能是通过您的查询
select*from tennismatch m join tenismatch_tennisset ms on m.id=ms.tennismatch_id join tennisset s on m.mapofsets_id=s.id其中m.id=1
您能帮我用一个语句删除行,请?您想从哪个表中删除行?我想从tennismatch表中删除行。您能帮我用一条语句删除行吗?您想从哪个表中删除行?我想从tennismatch表中删除行