1

我有这样的关系:

class Foo {
    static hasMany = [bars: Bar, things: Thing]
}

class Bar {
    // Has nothing to tie it back to Foo or Thing
}

class Thing {
    // Has nothing to tie it back to Foo or Bar
}

在此处输入图像描述

我有以下带有以下参数的查询,其中大部分用于使用 flexigrid 进行分页。此查询获取与viaThing的特定实例相关联的所有实例。因此,如果我的is实例期望我的查询返回并且:BarFooBarBar1Thing1Thing2

def obj = Bar.get( 1 ) // Get Bar1
def max = params.int( "max" ) ?: 100 // Default max returned results is 100 unless otherwise specified
def offset = params.int( "offset" ) ?: 0 // Default offset is 0 unless otherwise specified
def sortname = params.sortname ?: "id" // Default is id, but could be any member of Thing that is not a "hasMany"
def sortorder = params.sortorder ?: "ASC" // Default is ASC, but could be DESC

def namedParams = [ obj: obj, max: max, offset: offset ]

Thing.executeQuery( "SELECT DISTINCT f.things FROM Foo f INNER JOIN f.things things INNER JOIN f.bars bars WHERE bars =:obj ORDER BY ${sortname} ${sortorder}", namedParams )

Hibernate 不允许使用命名参数来指定ORDER BY子句,所以我只是插入了字符串。问题是结果没有按照我指定的顺序排列。使用ORDER BY idGrails 时告诉我id是模棱两可的。

知道变量sortname将始终是 的成员Thing,我如何指定要排序的内容?

我尝试过的一些事情:

ORDER BY Thing.id // Fail
ORDER BY f.things.id // Fail
ORDER BY things.id // FAIL!
4

1 回答 1

2

查询应该是:

SELECT DISTINCT thing FROM Foo f 
INNER JOIN f.things thing 
INNER JOIN f.bars bar 
WHERE bar = :obj 
ORDER BY thing.id

即您应该在 select 子句中使用实体的别名而不是其路径,并在 order by 子句中使用相同的别名。

于 2012-06-22T08:54:32.747 回答