如何在SQLAlchemy中执行多级预先加载？
[英]How can I do a multiple-level eager load in SQLAlchemy?
问题描述
I have many C s in a B and many B s in an A , and I have backref relationships defined. 
我有许多C在A S B和许多B S IN的A ，我已经backref定义的关系。 What I want to do is something like: 我想做的是：
a = A.query().options(subqueryload(A.b).subsubqueryload(B.c)
How should this be done? 该怎么做？
1 个解决方案
解决方案1
4 2014-02-27 19:32:59
直接来自subqueryload的文档：
qry = query(A).options(subqueryload(A.b).subqueryload(B.c))
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