Grails 2.0中带有新查询的参数 [英] Parameters with new where queries in Grails 2.0

问题描述

在Grails 2.0中定义where查询时可以使用参数吗？例如：

  def query = Book.where {
 id == it 
} 
 Book sub = query.find（5）
  

我试着运行该代码，但它抛出了MissingMethodException在电话中寻找。我也尝试在它之前定义一个变量，但它似乎并不工作（即使我知道它存在，find也会返回null）。

  Long someId = 5 
 def query = Book.where {
 id == someId 
} 
 Book sub = query.find（）
  

任何技巧？能够动态地改变查询的参数将是非常有用的。

（我知道我可以使用Book.get（5），但为了简单起见，这个看起来像是最简单的例子）

解决方案

似乎要做到这一点的方法是将闭包定义为detachCriteria， p>

  import grails.gorm。* 
 
 def callable = {id  - > 
 id == id 
} as DetachedCriteria< Book> 
 
 def query = Book.where（callable（id：5））
  

Is it possible to use parameters when defining a where query in Grails 2.0? For example:

def query = Book.where {
   id == it
}
Book sub = query.find(5)

I tried running that code, but it throws a MissingMethodException on the call to find. I also tried defining a variable before it, but it doesn't seem to work (as find returns null, even though I know it exists).

Long someId = 5
def query = Book.where {
   id == someId
}
Book sub = query.find()

Any tricks? Being able to dynamically change the parameters of the query would be extremely useful.

(I know I could just use Book.get(5), but for simplicity sake, this seemed like the easiest example to pick)

解决方案

Seems like the way to do this is to define a closure as detachCriteria,

import grails.gorm.*

def callable = { id -> 
    id == id
} as DetachedCriteria<Book>

def query = Book.where( callable( id: 5 ) )

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