hibernate - HQL加入许多子句 [英] hibernate - HQL joins on many clauses

问题描述

我一直在阅读Hibernate文档，但是我还没有找到任何解释如何执行以下操作的内容。

我有以下SQL代码'm试图转换为HQL：

  SELECT {msg。*}，{cmd。*} 
 FROM架构。消息AS msg 
 LEFT OUTER JOIN schema.send_commands AS cmd 
 ON cmd.message_key = msg.unique_key 
 AND（lower（cmd.status）IN（lower（'failed'））） 
 WHERE msg.sequence_received< 10; 
  

我遇到的主要问题是我无法在LQL OUTER JOIN。HQL允许我有
ON cmd.message_key = msg.unique_key
，但是如何将
AND子句2？

解决方案

c $ c> with 关键字，像这样（取决于你的映射）：

  SELECT m ，c 
 FROM消息m LEFT JOIN m.commands c WITH（lower（c.status）='failed'）
 WHERE m.sequenceReceived< 10 
   
 
        16.3。关联和连接  > 
  
I've been reading Hibernate documentation, but I haven't found anything that would explain how to do the following.

I have the following SQL code that I'm trying to convert to HQL:
SELECT {msg.*}, {cmd.*} 
FROM Schema.Messages AS msg 
  LEFT OUTER JOIN schema.send_commands AS cmd 
    ON cmd.message_key = msg.unique_key 
    AND ( lower(cmd.status) IN (lower('failed') ) ) 
WHERE msg.sequence_received < 10";
The mainissue I'm having is that I'm unable to have two clauses on a LEFT OUTER JOIN. HQL allows me to have 
     ON cmd.message_key = msg.unique_key
, but how do I add the 
AND clause 2?
解决方案
You can add extra join conditions using with keyword, something like this (depends on your mapping):
SELECT m, c 
FROM Message m LEFT JOIN m.commands c WITH (lower(c.status) = 'failed')
WHERE m.sequenceReceived < 10
See also:


16.3. Associations and joins


                        
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