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mysql-如何在Laravel中创建像波纹管这样的联接表

(mysql - How make a join table like bellow in laravel)

发布于 2020-11-28 09:22:36

Helllo,我想在laravel中的两个表之间进行联接,但是如果表B没有行查询,则返回null。我想要的就是这样。

table A

id user_id description
1    1      something
2    1       apple
3    2       cherry

table B

user_id post_id vote
(with no records initial)

result table

    id user_id description post_id  vote
    1    1      something    null   null
    2    1       apple       null   null
    3    2       cherry      null   null

我怎样才能做到这一点?在此先感谢你,我对英语不佳表示歉意。

Questioner
Mihăiță Nicolaescu
Viewed
0
OMR 2020-11-28 17:30:20

你应该使用leftJoin

 DB::table("tableA")->leftJoin("tableB","tableA.user_id",'=','tableB.user_id')
           ->select(["tableA.id as id",'tableA.user_id as user_id','description','post_id','vote'])->get();