Copyright: Kaka from https://blog.csdn.net/fangkang7 https://blog.csdn.net/fangkang7/article/details/90726684
author: Kaka
wechat: fangkangfk
When writing a one to one relationship model, reported this wrong, said price is not an object, this novice mistake is hard to find where the problem is
The reason for this problem is to find () to find the primary key id does not exist, this error will be reported
