Question

我的公司有很多客户。客户has_many消息。消息具有文本属性。

我正在尝试从其邮件的text属性中没有特定单词的客户那里获取customer_id列表。这是我到目前为止所做的：

company.customers.includes(:messages).references(:messages).where('messages.text NOT LIKE ?', "% summer %")

当我这样做并得到该组中的客户数量时，它是正确的数字（大约7500），但当我去采取这样的ID时：

company.customers.includes(:messages).references(:messages).where('messages.text NOT LIKE ?', "% summer %").pluck(:id).count

它返回80000结果，这是不正确的

我在做错了什么？

编辑：尝试回答错误：

PG::AmbiguousColumn: ERROR:  column reference "id" is ambiguous
LINE 1: SELECT id FROM "customers" LEFT OUTER JOIN "messages" ON "me...
               ^
: SELECT id FROM "customers" LEFT OUTER JOIN "messages" ON "messages"."customer_id" = "customers"."id" WHERE "customers"."company_id" = $1 AND (messages.text NOT LIKE '% summer %')
PG::AmbiguousColumn: ERROR:  column reference "id" is ambiguous
LINE 1: SELECT id FROM "customers" LEFT OUTER JOIN "messages" ON "me...
               ^
: SELECT id FROM "customers" LEFT OUTER JOIN "messages" ON "messages"."customer_id" = "customers"."id" WHERE "customers"."company_id" = $1 AND (messages.text NOT LIKE '% summer %')
ActiveRecord::StatementInvalid: PG::AmbiguousColumn: ERROR:  column reference "id" is ambiguous
LINE 1: SELECT id FROM "customers" LEFT OUTER JOIN "messages" ON "me...

Answer 1

尝试：

company.customers.includes(:messages).references(:messages).where('messages.text NOT LIKE ?', "% summer %").distinct.pluck(:id).count

Answer 2

将ids链接到查询的末尾：

company.customers.includes(:messages).references(:messages).where('messages.text NOT LIKE ?', "% summer %").ids

您还应该能够删除引用：

company.customers.includes(:messages).where('messages.text NOT LIKE ?', "% summer %").ids

Answer 3

有相同的＆＃34; id＆＃34;查询中的字段（客户，消息），因此您需要添加一个id字段来对其进行排序。您可以添加重新订购（：id），以便按客户ID为您排序。

试试这个：

company.customers.includes(:messages).references(:messages).where('messages.text NOT LIKE ?', "% summer %").reorder(:id).pluck(:id)

如何根据与另一个模型的关联从模型中获取ID列表

3 个答案: