java - 加入 Hibernate HQL

Question

我正在尝试对 hql hibernate(版本 3.5.3)进行查询，该查询包括不同表(4 个表)之间的多个连接。这是查询:

     SELECT (lot of stuff) 
     FROM InvestigationRule as ir
     JOIN InvestigationFormula as if ON (ir.tb33InvestigationFormula=if.idInvestigationFormula) 
     JOIN InvestigationEvent as ie ON (ir.tb27InvestigationEvent=ie.idInvestigationEvent) 
     JOIN InvestigationSectionEvent as ise ON (ie.eventSection=ise.sectionEventsCod)

我第一次遇到语法错误，谁能帮我解决这个问题，谢谢。

ps:我知道即使不使用 JOIN 命令我也可以进行连接，这是原始查询:

    SELECT (lot of stuff)  
    FROM InvestigationRule AS ir, 
         InvestigationEvent as ie, 
         InvestigationSectionEvent as ise, 
         InvestigationFormula as if 
          WHERE ir.dateValidityEnd is null 
          AND ir.tb27InvestigationEvent = ie.idInvestigationEvent 
          AND ir.tb33InvestigationFormula = if.idInvestigationFormula 
          AND ie.eventSection = ise.sectionEventsCod 

但我不能使用这种形式，因为它在 MySql 数据库上创建了多个 CROSS JOIN(s)，这是不好的。

Answer 1

if 是 SQL 中的关键字，因此您必须更改别名:

SELECT (lot of stuff) 
     FROM InvestigationRule as ir
     JOIN InvestigationFormula as iform ON (ir.tb33InvestigationFormula=iform.idInvestigationFormula) 
     JOIN InvestigationEvent as ie ON (ir.tb27InvestigationEvent=ie.idInvestigationEvent) 
     JOIN InvestigationSectionEvent as ise ON (ie.eventSection=ise.sectionEventsCod)

HQL 看起来像:

SELECT (lot of stuff) 
     FROM InvestigationRule ir
     JOIN ir tb33InvestigationFormula iform
     JOIN ir.tb27InvestigationEvent ie 
     JOIN  ie.eventSection ise