双向o2m/m2o在SQL效率上优于单向o2m？
使用这 2 个持久性 CFC 例如：
// Cat.cfc
component persistent="true" {
property name="id" fieldtype="id" generator="native";
property name="name";
}
// Owner.cfc
component persistent="true" {
property name="id" fieldtype="id" generator="native";
property name="cats" type="array" fieldtype="one-to-many" cfc="cat" cascade="all";
}
当一对多（单向）时注意：单向上的 inverse=true 将产生不需要的结果：
insert into cat (name) values (?)
insert into Owner default values
update cat set Owner_id=? where id=?
当一对多/多对一（双向）时-direction, inverse=true on Owner.cats)：
insert into Owner default values
insert into cat (name, ownerId) values (?, ?)
这是否意味着首选设置双向 o2m/m2o 关系，因为插入实体的 SQL 效率更高？
Use these 2 persistent CFCs for example:
// Cat.cfc
component persistent="true" {
property name="id" fieldtype="id" generator="native";
property name="name";
}
// Owner.cfc
component persistent="true" {
property name="id" fieldtype="id" generator="native";
property name="cats" type="array" fieldtype="one-to-many" cfc="cat" cascade="all";
}
When one-to-many (unidirectional) Note: inverse=true on unidirectional will yield undesired result:
insert into cat (name) values (?)
insert into Owner default values
update cat set Owner_id=? where id=?
When one-to-many/many-to-one (bi-directional, inverse=true on Owner.cats):
insert into Owner default values
insert into cat (name, ownerId) values (?, ?)
Does that mean setting up bi-directional o2m/m2o relationship is preferred 'cause the SQL for inserting the entities is more efficient?
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“首选”很复杂。
虽然对于“猫”来说，默认所有者的想法没有意义，但对于工厂或商店的情况可能有意义，一旦创建“产品”，它就会获得“工厂”的默认“位置”。
'Preferred' is complicated.
While for 'cat' the idea of a default owner doesn't make sense, it might do for a factory or shop situation, where once a 'product' is created it get's a default 'location' of 'the factory'.