刷新页面时Grails中出现奇怪的GORM行为(F5)

Question

我有一个实体(作者)和一个控制器动作,呈现所有作者.

def index = {
    def list = Author.list()
    render(view: 'index', model: ['allauthors' : list])
}

呈现页面时,将按预期执行单个查询:

Hibernate: 
  select
    this_.id as id0_0_,
    this_.version as version0_0_,
    this_.name as name0_0_
  from
    author this_

但是,当我按下Refresh(F5)然后为每个作者执行一个select语句(这里我有3个作者):

Hibernate: 
select
    author0_.id as id0_0_,
    author0_.version as version0_0_,
    author0_.name as name0_0_
from
    author author0_ 
where
    author0_.id=?
Hibernate: 
select
    author0_.id as id0_0_,
    author0_.version as version0_0_,
    author0_.name as name0_0_
from
    author author0_ 
where
    author0_.id=?
Hibernate: 
select
    author0_.id as id0_0_,
    author0_.version as version0_0_,
    author0_.name as name0_0_
from
    author author0_ 
where
    author0_.id=?

为什么会这样？

Answer 1

看起来这与查询缓存有关。如果你有

cache.use_query_cache = true

在您的 Datasource.groovy 中，但没有在域类中设置缓存，缓存似乎会逐出每个条目上的所有条目list()，并且必须重新缓存每个条目（只是猜测）。

如果您向域添加缓存，则多个选择就会消失 - 事实上，当我在添加以下内容后刷新时，不会执行任何选择：

static mapping = {
    cache true
}