根据多个表的条件显示列

Question

我的目的是通过在donation_status表中给出status ='yes'的条件来打印邮件ID，地址和宠物类型，pet_details的id =捐赠者的pet_id和收件人的pet_id以及成员的ID =捐赠者广告的member_id member_id =收件人。

简单来说，我想显示捐赠者和接受者的详细信息以及捐赠宠物的类型

图1：表格 - 成员和捐赠者 图2：表格 - 收件人，donation_status，pet_details

我试过的查询是 select members.mail_id,members.address,pet_details.type from members,pet_details,donor,recipient,donation_status where members.id in (select pet_id from members,pet_details,donor,recipient,donation_status where status = 'yes' in (select member_id from donor,members,pet_details,donor,recipient where donor.member_id = recipient.member_id in (select pet_id from members,pet_details,donor,recipient where pet_id.donation_status = id.pet_details)))

我得到的错误是，

ERROR 1066（42000）：不是唯一的表/别名：'donor'

Answer 1

执行此查询的正确方法是使用JOIN：

SELECT m1.mail_id AS donor, m1.address AS `donor address`, m2.mail_id AS recipient, m2.address AS `recipient_address`, pet_details.type as `pet type`
FROM members m1
JOIN donor ON donor.member_id = m1.id
JOIN recipient ON recipient.pet_id = donor.pet_id
JOIN donation_status ON donation_status.pet_id = donor.pet_id
JOIN members m2 ON m2.id = recipient.member_id
JOIN pet_details ON pet_details.id = donor.pet_id
WHERE donation_status.status = 'yes'

输出（似乎是一名成员向自己捐赠了一只狗）：

donor               donor address           recipient               recipient_address       pet type    
mn.sha222@gmail.com Gandhinagar Coimbatore  mn.sha222@gmail.com     Gandhinagar Coimbatore  dog