如何在不使用联接的情况下在array_agg中使用子查询

Question

我有一个查询，我想使用联接写 wihout ，并从另一个表中将所有电话号码合并在一起。 电话号码通过ink_id字段链接在一起。

我尝试了这些查询，但是它们都给了我一个语法错误。

select
    ink.fullname,
    array_agg(select phone_number from phone_numbers where phone_numbers.ink_id = ink.id) as _phones
from
    ink

或

select
    ink.fullname,
    select(array_agg(phone_number) from phone_numbers where phone_numbers.ink_id = ink.id) as _phones
from
    ink

墨水表

+-----+------------+
| id  |  fullname  |
+-----+------------+
| 567 | John Smith |
| 159 | Caleb Doe  |
| 333 | Bill Gates |
+-----+------------+

电话号码表

+----+--------+--------------+
| id | ink_id | phone_number |
+----+--------+--------------+
|  1 |    333 |    516519899 |
|  2 |    159 |    216584989 |
|  3 |    333 |    123149849 |
+----+--------+--------------+

所以结果应该是

+-----+------------+----------------------+
| id  |  fullname  |    _phone_numbers    |
+-----+------------+----------------------+
| 567 | John Smith |                      |
| 159 | Caleb Doe  | 216584989            |
| 333 | Bill Gates | 516519899, 123149849 |
+-----+------------+----------------------+

Answer 1

如果使用正确的语法，第二种方法将起作用：

select ink.fullname,
       (select array_agg(pn.phone_number)
        from phone_numbers pn
        where pn.ink_id = ink.id
       ) as _phones
from ink;

子查询需要用括号括起来。