Question

我有两个表（EAV关系），Customer（id，name）和CustomerVarchar（id，customer_id，{ {1}}，attribute_id）关系如下。

value hasMany Customer

CustomerVarchar belongsTo CustomerVarchar

我想根据Customer中具有特定值的两行在Customer中选择一行。更具体地说，我想在CustomreVarchar中检索具有以下条件的这两个关联行的行（必须在Customer中包含两个关联的行）：

CustomerVarchar

这可能吗？

Answer 1

您可以使用以下命令从customer_id表中返回customerVarchar的所有属性和值：

select customer_id
from customerVarchar
group by customer_id
having 
  sum(case when attribute_id = 5 and value = 'John' then 1 else 0 end) > 0
  and sum(case when attribute_id = 7 and value = 'Doe' then 1 else 0 end) > 0;

然后，您可以将其加入到您的customer表中，以便向客户返回该数据：

select c.id, c.name
from customer c
inner join
(
  select customer_id
  from customerVarchar
  group by customer_id
  having 
    sum(case when attribute_id = 5 and value = 'John' then 1 else 0 end) > 0
    and sum(case when attribute_id = 7 and value = 'Doe' then 1 else 0 end) > 0
) v
  on c.id = v.customer_id;

请参阅SQL Fiddle with Demo

根据EAV中相关行中的值选择行

1 个答案: