Grails使用具有3x +逻辑参数的动态查找器 [英] Grails using dynamic finders with 3x+ logical arguments

问题描述

我成功地使用Hibernate中的动态查找器在数据库中进行搜索：

I sucessfully managed to search in the database using this dynamic finder from Hibernate:

def temp = User.findByNameAndStreet("name", "street")

尽管我需要一个这样的triple逻辑参数：

Although, i need a tripple logical argument like this:

def temp = User.findByNameAndStreetAndCity("name", "street", "city")

任何简单的方法来做？

推荐答案

The Grails dynamic finders don't support more than two predicates. This is because it's not clear whether

User.findByNameAndAgeOrGender('foo', 12, 'm')

意思是：

(name == 'foo' && age == 12) || gender == 'm'

或这个：

name == 'foo' && (age == 12 || gender == 'm')

诚然，如果谓词总是相结合与和或或。

Admittedly if the predicates are always combined with And or Or.

更新：自Grails 1.4以来，您可以拥有无​​限数量的谓词，如果它们都与和或或

Update: since Grails 1.4 you can have an unlimited number of predicates if they're all combined with either And or Or

相反，您可以使用 findWhere 或 findAllWhere （取决于您是否只想要第一个结果或所有结果）。这两个都支持无限数量的谓词，我假定与和相结合，例如：

Instead, you can use either findWhere or findAllWhere (depending on whether you want just the first result or all results). Both of these support an unlimited number of predicates which I assume are combined with And, for example:

User.findAllWhere(name: "foo", age: 12, gender: 'm')

这篇关于Grails使用具有3x +逻辑参数的动态查找器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！