T-SQL查询多对多

Question

我有3张桌子：

doctors:
-----------
id
name

language:
-----------
id
name

languageDoctors:
----------------
doctor_id
language_id

我想返回带有医生姓名的JSON，然后返回医生拥有的多种语言。

Answer 1

好吧，您可以使用for json path来构造json：

select d.*,
       (select l.name as language
        from doctor_languages dl join
             languages l
             on dl.language_id = l.language_id
        where dl.doctor_id = d.doctor_id
        for json path
       ) as languages
from doctors d;

Here是db <>小提琴。