表Customer中peopleInCharge列和表People关联
实际业务是Customer新客户增加时peopleInCharge未知,此时允许列peopleInCharge为空,以后再修改设置peopleInCharge
问题1:是A增加时如何设置使其能插入空值?
如上设置在保存时报错
object references an unsaved transient instance - save the transient instance before flushing: 省略.People
问题2:如果数据库直接增加一条peopleInCharge为null的数据,查询时无法显示数据
查询语句此2表格是inner join (上面这种情况下只有left join才可查询出来)