加入查詢返回數據

我有以下查詢返回數據只有當連接存在。我如何從最後一個連接的表（#__unis）數據返回，即使這些表之間沒有關係而不寫另一個查詢？的加入查詢返回數據

select * from #__unis_faculties AS faculty 
    join #__unis_subjects AS subject ON subject.faculty = faculty.id 
    join #__unis AS uni ON uni.id= subject.university 
    where uni.id = 1

表結構http://sqlfiddle.com/#!2/19add

來源

2013-07-06 fefe

使用LEFT JOIN代替join

select * from #__unis_faculties AS faculty 
join #__unis_subjects AS subject ON subject.faculty = faculty.id 
right join #__unis AS uni ON uni.id= subject.university 
where uni.id = 1

來源

2013-07-06 14:48:41

我一直在嘗試之前，但該數組爲空 – fefe

可以爲您提供一個小提琴的例子？ –

我開始創建它 – fefe

試試這個..

select * from #__unis_faculties AS faculty 
join #__unis_subjects AS subject ON subject.faculty = faculty.id 
left join #__unis AS uni ON (uni.id= subject.university AND uni.id = 1)

來源

2013-07-06 18:43:27 Manu

加入查詢返回數據

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