Java 试图理解Hibernate抓取策略

目前，hibernate V3.5.1在请求期间执行的SQL语句大量增加，这给我带来了严重的性能问题。因此，我试图深入了解细节，以了解急切抓取的细节

基本上，问题似乎源于这样一个问题：我们使用的匹配实体指的是两个匹配的概要文件实体。hibernate似乎只会通过连接来获取一个或多个配置文件，但不能同时获取这两个配置文件。另一个由select加载

[MatchingData] ---- searchingProfile--> [ProfileData] ---- searchData --> [SearchData]
                 |
                 +- potentialMatch ---> [ProfileData] ---- searchData --> [SearchData]

所有关联都由FetchMode.Join和@ManyToOne@OneToOneoptional=false，fetch=FetchType.EAGER，cascade=

我已经建立了一个简单的例子，用HQL和Criterias测试通过hibernate获取匹配数据的各种方法。不幸的是，锅炉铭牌代码太大，无法向她详细发布。我可以按要求提供

测试是

System.out.println------------这应该是一个SQL语句？----------； 列表结果1=hibernateTemplate.find 从匹配数据； openSession.clear； System.out.println------------这应该是一个SQL语句？----------； List result2=hibernateTemplate.find 来自MatchingData，其中potentialMatch.firstName=无效的 openSession.clear； System.out.println------------这应该是一个SQL语句？----------； Criteria matchingDataCriteria1=openSession.createCriteriaMatchingData.class； matchingDataCriteria1.createCriteriapotentialMatch.addRestrictions.eqfirstName，FIRSTNAME\u TEST\u PM； matchingDataCriteria1.list； openSession.clear； System.out.println------------这是一个SQL语句？----------； Criteria matchingDataCriteria2=openSession.createCriteriaMatchingData.class； matchingDataCriteria2.list； openSession.clear； 数据库中有2个匹配数据和3个涉及的ProfileData，结果是

-------------------- this should be a single SQL statement ? ------------------------
Hibernate: select matchingda0_.id as id3_, matchingda0_.potentialMatch as potentia2_3_, matchingda0_.searchingProfile as searchin3_3_ from MatchingData matchingda0_
Hibernate: select profiledat0_.id as id0_3_, profiledat0_.firstName as firstName0_3_, profiledat0_.kontaktSparkasse_BLZ as kontaktS5_0_3_, profiledat0_.lastName as lastName0_3_, profiledat0_.profileType as profileT4_0_3_, profiledat0_.searchData_id as searchData6_0_3_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_, institutsd2_.BLZ as BLZ2_1_, institutsd2_.name as name2_1_, institutsd2_.parentHub_BLZ as parentHub3_2_1_, searchdata3_.id as id1_2_, searchdata3_.fakeContent as fakeCont2_1_2_ from ProfileData profiledat0_ inner join InstitutsData institutsd1_ on profiledat0_.kontaktSparkasse_BLZ=institutsd1_.BLZ left outer join InstitutsData institutsd2_ on institutsd1_.parentHub_BLZ=institutsd2_.BLZ left outer join SearchData searchdata3_ on profiledat0_.searchData_id=searchdata3_.id where profiledat0_.id=?
Hibernate: select profiledat0_.id as id0_3_, profiledat0_.firstName as firstName0_3_, profiledat0_.kontaktSparkasse_BLZ as kontaktS5_0_3_, profiledat0_.lastName as lastName0_3_, profiledat0_.profileType as profileT4_0_3_, profiledat0_.searchData_id as searchData6_0_3_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_, institutsd2_.BLZ as BLZ2_1_, institutsd2_.name as name2_1_, institutsd2_.parentHub_BLZ as parentHub3_2_1_, searchdata3_.id as id1_2_, searchdata3_.fakeContent as fakeCont2_1_2_ from ProfileData profiledat0_ inner join InstitutsData institutsd1_ on profiledat0_.kontaktSparkasse_BLZ=institutsd1_.BLZ left outer join InstitutsData institutsd2_ on institutsd1_.parentHub_BLZ=institutsd2_.BLZ left outer join SearchData searchdata3_ on profiledat0_.searchData_id=searchdata3_.id where profiledat0_.id=?
Hibernate: select profiledat0_.id as id0_3_, profiledat0_.firstName as firstName0_3_, profiledat0_.kontaktSparkasse_BLZ as kontaktS5_0_3_, profiledat0_.lastName as lastName0_3_, profiledat0_.profileType as profileT4_0_3_, profiledat0_.searchData_id as searchData6_0_3_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_, institutsd2_.BLZ as BLZ2_1_, institutsd2_.name as name2_1_, institutsd2_.parentHub_BLZ as parentHub3_2_1_, searchdata3_.id as id1_2_, searchdata3_.fakeContent as fakeCont2_1_2_ from ProfileData profiledat0_ inner join InstitutsData institutsd1_ on profiledat0_.kontaktSparkasse_BLZ=institutsd1_.BLZ left outer join InstitutsData institutsd2_ on institutsd1_.parentHub_BLZ=institutsd2_.BLZ left outer join SearchData searchdata3_ on profiledat0_.searchData_id=searchdata3_.id where profiledat0_.id=?
-------------------- this should be a single SQL statement ? ------------------------
Hibernate: select matchingda0_.id as id3_, matchingda0_.potentialMatch as potentia2_3_, matchingda0_.searchingProfile as searchin3_3_ from MatchingData matchingda0_ cross join ProfileData profiledat1_ where matchingda0_.potentialMatch=profiledat1_.id and (profiledat1_.firstName is not null)
Hibernate: select profiledat0_.id as id0_3_, profiledat0_.firstName as firstName0_3_, profiledat0_.kontaktSparkasse_BLZ as kontaktS5_0_3_, profiledat0_.lastName as lastName0_3_, profiledat0_.profileType as profileT4_0_3_, profiledat0_.searchData_id as searchData6_0_3_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_, institutsd2_.BLZ as BLZ2_1_, institutsd2_.name as name2_1_, institutsd2_.parentHub_BLZ as parentHub3_2_1_, searchdata3_.id as id1_2_, searchdata3_.fakeContent as fakeCont2_1_2_ from ProfileData profiledat0_ inner join InstitutsData institutsd1_ on profiledat0_.kontaktSparkasse_BLZ=institutsd1_.BLZ left outer join InstitutsData institutsd2_ on institutsd1_.parentHub_BLZ=institutsd2_.BLZ left outer join SearchData searchdata3_ on profiledat0_.searchData_id=searchdata3_.id where profiledat0_.id=?
Hibernate: select profiledat0_.id as id0_3_, profiledat0_.firstName as firstName0_3_, profiledat0_.kontaktSparkasse_BLZ as kontaktS5_0_3_, profiledat0_.lastName as lastName0_3_, profiledat0_.profileType as profileT4_0_3_, profiledat0_.searchData_id as searchData6_0_3_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_, institutsd2_.BLZ as BLZ2_1_, institutsd2_.name as name2_1_, institutsd2_.parentHub_BLZ as parentHub3_2_1_, searchdata3_.id as id1_2_, searchdata3_.fakeContent as fakeCont2_1_2_ from ProfileData profiledat0_ inner join InstitutsData institutsd1_ on profiledat0_.kontaktSparkasse_BLZ=institutsd1_.BLZ left outer join InstitutsData institutsd2_ on institutsd1_.parentHub_BLZ=institutsd2_.BLZ left outer join SearchData searchdata3_ on profiledat0_.searchData_id=searchdata3_.id where profiledat0_.id=?
Hibernate: select profiledat0_.id as id0_3_, profiledat0_.firstName as firstName0_3_, profiledat0_.kontaktSparkasse_BLZ as kontaktS5_0_3_, profiledat0_.lastName as lastName0_3_, profiledat0_.profileType as profileT4_0_3_, profiledat0_.searchData_id as searchData6_0_3_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_, institutsd2_.BLZ as BLZ2_1_, institutsd2_.name as name2_1_, institutsd2_.parentHub_BLZ as parentHub3_2_1_, searchdata3_.id as id1_2_, searchdata3_.fakeContent as fakeCont2_1_2_ from ProfileData profiledat0_ inner join InstitutsData institutsd1_ on profiledat0_.kontaktSparkasse_BLZ=institutsd1_.BLZ left outer join InstitutsData institutsd2_ on institutsd1_.parentHub_BLZ=institutsd2_.BLZ left outer join SearchData searchdata3_ on profiledat0_.searchData_id=searchdata3_.id where profiledat0_.id=?
-------------------- this should be a single SQL statement ? ------------------------
Hibernate: select this_.id as id3_5_, this_.potentialMatch as potentia2_3_5_, this_.searchingProfile as searchin3_3_5_, profiledat1_.id as id0_0_, profiledat1_.firstName as firstName0_0_, profiledat1_.kontaktSparkasse_BLZ as kontaktS5_0_0_, profiledat1_.lastName as lastName0_0_, profiledat1_.profileType as profileT4_0_0_, profiledat1_.searchData_id as searchData6_0_0_, institutsd4_.BLZ as BLZ2_1_, institutsd4_.name as name2_1_, institutsd4_.parentHub_BLZ as parentHub3_2_1_, institutsd5_.BLZ as BLZ2_2_, institutsd5_.name as name2_2_, institutsd5_.parentHub_BLZ as parentHub3_2_2_, searchdata6_.id as id1_3_, searchdata6_.fakeContent as fakeCont2_1_3_, profiledat7_.id as id0_4_, profiledat7_.firstName as firstName0_4_, profiledat7_.kontaktSparkasse_BLZ as kontaktS5_0_4_, profiledat7_.lastName as lastName0_4_, profiledat7_.profileType as profileT4_0_4_, profiledat7_.searchData_id as searchData6_0_4_ from MatchingData this_ inner join ProfileData profiledat1_ on this_.potentialMatch=profiledat1_.id left outer join InstitutsData institutsd4_ on profiledat1_.kontaktSparkasse_BLZ=institutsd4_.BLZ left outer join InstitutsData institutsd5_ on institutsd4_.parentHub_BLZ=institutsd5_.BLZ left outer join SearchData searchdata6_ on profiledat1_.searchData_id=searchdata6_.id inner join ProfileData profiledat7_ on this_.searchingProfile=profiledat7_.id where profiledat1_.firstName=?
Hibernate: select institutsd0_.BLZ as BLZ2_1_, institutsd0_.name as name2_1_, institutsd0_.parentHub_BLZ as parentHub3_2_1_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_ from InstitutsData institutsd0_ left outer join InstitutsData institutsd1_ on institutsd0_.parentHub_BLZ=institutsd1_.BLZ where institutsd0_.BLZ=?
Hibernate: select searchdata0_.id as id1_0_, searchdata0_.fakeContent as fakeCont2_1_0_ from SearchData searchdata0_ where searchdata0_.id=?
Hibernate: select searchdata0_.id as id1_0_, searchdata0_.fakeContent as fakeCont2_1_0_ from SearchData searchdata0_ where searchdata0_.id=?
-------------------- this should be a a single SQL statement ? ------------------------
Hibernate: select this_.id as id3_5_, this_.potentialMatch as potentia2_3_5_, this_.searchingProfile as searchin3_3_5_, profiledat2_.id as id0_0_, profiledat2_.firstName as firstName0_0_, profiledat2_.kontaktSparkasse_BLZ as kontaktS5_0_0_, profiledat2_.lastName as lastName0_0_, profiledat2_.profileType as profileT4_0_0_, profiledat2_.searchData_id as searchData6_0_0_, institutsd3_.BLZ as BLZ2_1_, institutsd3_.name as name2_1_, institutsd3_.parentHub_BLZ as parentHub3_2_1_, institutsd4_.BLZ as BLZ2_2_, institutsd4_.name as name2_2_, institutsd4_.parentHub_BLZ as parentHub3_2_2_, searchdata5_.id as id1_3_, searchdata5_.fakeContent as fakeCont2_1_3_, profiledat6_.id as id0_4_, profiledat6_.firstName as firstName0_4_, profiledat6_.kontaktSparkasse_BLZ as kontaktS5_0_4_, profiledat6_.lastName as lastName0_4_, profiledat6_.profileType as profileT4_0_4_, profiledat6_.searchData_id as searchData6_0_4_ from MatchingData this_ inner join ProfileData profiledat2_ on this_.potentialMatch=profiledat2_.id left outer join InstitutsData institutsd3_ on profiledat2_.kontaktSparkasse_BLZ=institutsd3_.BLZ left outer join InstitutsData institutsd4_ on institutsd3_.parentHub_BLZ=institutsd4_.BLZ left outer join SearchData searchdata5_ on profiledat2_.searchData_id=searchdata5_.id inner join ProfileData profiledat6_ on this_.searchingProfile=profiledat6_.id
Hibernate: select institutsd0_.BLZ as BLZ2_1_, institutsd0_.name as name2_1_, institutsd0_.parentHub_BLZ as parentHub3_2_1_, institutsd1_.BLZ as BLZ2_0_, institutsd1_.name as name2_0_, institutsd1_.parentHub_BLZ as parentHub3_2_0_ from InstitutsData institutsd0_ left outer join InstitutsData institutsd1_ on institutsd0_.parentHub_BLZ=institutsd1_.BLZ where institutsd0_.BLZ=?
Hibernate: select searchdata0_.id as id1_0_, searchdata0_.fakeContent as fakeCont2_1_0_ from SearchData searchdata0_ where searchdata0_.id=?
Hibernate: select searchdata0_.id as id1_0_, searchdata0_.fakeContent as fakeCont2_1_0_ from SearchData searchdata0_ where searchdata0_.id=?

据我所知：HQL find本身并没有进行快速抓取，而是通过单独的选择加载ProfileData和进一步的数据。当然，我可以添加一些急切的抓取提示，但在复杂的数据结构中这是相当麻烦的

Criteria查询管理在一条语句中加载potentialMatch的一侧，同时加载其SearchData。另一侧的searchingProfile也会被提取，但次级实体SearchData和其他元素随后会通过显式选择提取

---

问题：有没有一种优雅的方法可以确保在一个swift中加载数据？

您看过fetch配置文件了吗？