Grails 动态地将 gorm 子查询添加到现有查询中

Question

我想有一个用于构建查询的实用程序，以便我可以为常见查询添加特异性，而不是一遍又一遍地硬编码类似的查询。例如：

DetachedCriteria query = DeviceConfiguration.where { ... }
while(query.list(max: 2).size() > 1) QueryUtil.addConstraint(query, newConstraint)

但是我在处理涉及多对多关系的查询时遇到了麻烦。

如果我的域类是：

class StringDescriptor {
    String name
    String stringValue
    static hasMany = [ deviceConfigurations: DeviceConfiguration ]
    static belongsTo = DeviceConfiguration
}
class DeviceConfiguration {
    Integer setting1
    Integer setting2
    static hasMany = [ stringDescriptors: StringDescriptor ]
}

我的设备配置如下所示：

DeviceConfiguration hondaAccord = new DeviceConfiguration(setting1: 1, setting2: 1)
DeviceConfiguration hondaCivic = new DeviceConfiguration(setting1: 2, setting2: 2)
DeviceConfiguration accord = new DeviceConfiguration(setting1: 3, setting2: 3)
StringDescriptor hondaDescriptor = new StringDescriptor(name: "make", stringValue: "honda")
StringDescriptor civicDescriptor = new StringDescriptor(name: "model", stringValue: "civic")
StringDescriptor accordDescriptor = new StringDescriptor(name: "model", stringValue: "accord")
hondaAccord.addToStringDescriptors(hondaDescriptor)
hondaAccord.addToStringDescriptors(accordDescriptor)
hondaCivic.addToStringDescriptors(hondaDescriptor)
hondaCivic.addToStringDescriptors(civicDescriptor)
accord.addToStringDescriptors(accordDescriptor)
hondaAccord.save(failOnError: true)
hondaCivic.save(failOnError: true)
accord.save(failOnError: true, flush: true)

我希望能够做到这一点：

def query = DeviceCollector.where{ stringDescriptors {name =~ "make" & stringValue =~ "honda"} }
if(query.list(max: 2)?.size() > 1)
    def query2 = query.where { stringDescriptors {name =~ "model" & stringValue =~ "civic"} }
if(query2.list(max: 2)?.size() > 1) 
    //...

但这不起作用 - query2 给出的结果与第一个查询相同。然而，当我这样做时，它完美地工作：

def query = DeviceCollector.where{ stringDescriptors {name =~ "make" & stringValue =~ "honda"} }
if(query.list(max: 2)?.size() > 1)
    def query2 = query.where { eq('setting1', 1) }
if(query.list(max: 2)?.size() > 1)
    def query3 = query.build { eq('setting2', 1) }

请告知:(

感谢注射器进行编辑

现在我的域名包括这个：

class DeviceConfiguration {
    //...
    static namedQueries = {
        byStringDescriptor { String name, String value ->
            stringDescriptors {
                ilike 'name', name
                ilike 'stringValue', value
            }
        }
    }
}

我尝试将查询串在一起，如下所示：

//Lists hondaAccord and hondaCivic
DeviceConfiguration.byStringDescriptor("make", "honda").list()
//Lists hondaAccord and accord
DeviceConfiguration.byStringDescriptor("model", "accord").list()
// LISTS NOTHING... BUT WHYYYYY?
DeviceConfiguration.byStringDescriptor("make", "honda").byStringDescriptor("model", "accord").list()

我很困惑。又一次。

编辑感谢注射器的更新答案

是的，这是对我有用的命名查询：

class DeviceConfiguration {
    //...
    static namedQueries = {
        byStringDescriptor { List<StringDescriptor> descriptors ->
            sizeEq('stringDescriptors', descriptors.size())
            stringDescriptors {
                or {
                    for(descriptor in descriptors) {
                        and {
                            ilike 'name', descriptor.name
                            ilike 'stringValue', descriptor.stringValue
                        }
                    }
                }
            }
        }
    }
}

结果(YAYYY(:)...

StringDescriptor hondaDescriptor = new StringDescriptor(name: "make", stringValue: "honda")
StringDescriptor accordDescriptor = new StringDescriptor(name: "model", stringValue: "accord")
//returns nothing - **check**
def hondaQuery = DeviceConfiguration.byStringDescriptor([hondaDescriptor]).list()
//returns accord configuration - **check**
def accordQuery = DeviceConfiguration.byStringDescriptor([accordDescriptor]).list()
//returns just the hondaAccord configuration - **YESSSSSS**
def hondaAccordQuery = DeviceConfiguration.byStringDescriptorUsingOr([hondaDescriptor, accordDescriptor]).listDistinct()

注射器是我最喜欢的人。

Answer 1

使用 criteria query 或 named queries . 它们都允许更好的链接

class DeviceConfiguration {
  static namedQueries = {
    byDescriptors { List vals -> 
      stringDescriptors { 
        or{
          for( def tuple in vals ){
            and{
              ilike 'name', "%${tuple[ 0 ]}%"
              ilike 'stringValue', "%${tuple[ 1 ]}%"
            }
          }
        }
      }
    }
  }       
}

因此，您可以致电：

DeviceConfiguration.byDescriptors( [ [ 'make', 'honda' ], [ 'model', 'accord' ] ] ).findAllBySetting1( 10 )

你应该知道，什么合相是合适的and或or

更新 2

有这么多and，你什么也找不到......

如果你启动一个像blah( honda, accord ).list()这样的查询，它会尝试找到带有name='honda' AND name='accord'的字符串描述符，这是不可能的，所以它不返回任何结果！

这就是为什么我倾向于认为，您的域模型根本不允许此类查询 - 即使在SQL级别也是如此。

您的属性应清晰可辨，以便您可以通过本田(类型"制造"(和雅阁(类型"模型"(找到它不应该在"模型"中寻找"本田"。

单个DeviceConfiguration实例可以包含同一type的多个StringDescriptor吗？