@Test

    public void test11(){

        Session ss=HibernateUtil.getSession();

        //根据员工名称(SCOTT)找到和他所在的部门的其他员工的信息

        String hql=" select e from Emp e inner join e.dept";//下面一条等效

        //String hql="from Emp e inner join fetch e.dept";

        Query qr=ss.createQuery(hql);

        List<Emp> el =qr.list();

        System.out.println(el.size());

        for (Emp emp : el) {

            System.out.println(emp);

        }

        HibernateUtil.closeResource(ss);

    }

inner join代码

inner join输出27条结果,但是分块输出,条件查询也执行了几次.

Hibernate:

    select

        emp0_.empno as empno1_1_,

        emp0_.ename as ename2_1_,

        emp0_.job as job3_1_,

        emp0_.mgr as mgr4_1_,

        emp0_.hiredate as hiredate5_1_,

        emp0_.sal as sal6_1_,

        emp0_.comm as comm7_1_,

        emp0_.deptno as deptno8_1_

    from

        EMP2 emp0_

    inner join

        DEPT2 dept1_

            on emp0_.deptno=dept1_.deptno

24

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=7369, eName=SMITH, job=CLERK, mgr=7902, hireDate=1980-12-17 00:00:00.0, sal=800.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=7499, eName=ALLEN, job=SALESMAN, mgr=7698, hireDate=1981-02-20 00:00:00.0, sal=1600.0, comm=300.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7521, eName=WARD, job=SALESMAN, mgr=7698, hireDate=1981-02-22 00:00:00.0, sal=1250.0, comm=500.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7566, eName=JONES, job=MANAGER, mgr=7839, hireDate=1981-04-02 00:00:00.0, sal=2975.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7654, eName=MARTIN, job=SALESMAN, mgr=7698, hireDate=1981-09-28 00:00:00.0, sal=1250.0, comm=1400.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7698, eName=BLAKE, job=MANAGER, mgr=7839, hireDate=1981-05-01 00:00:00.0, sal=2850.0, comm=null, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=7782, eName=CLARK, job=MANAGER, mgr=7839, hireDate=1981-06-09 00:00:00.0, sal=2450.0, comm=null, dept=Dept [deptNo=10, dName=ACCOUNTING, loc=NEW YORK

]]

Emp [empNo=7788, eName=SCOTT, job=ANALYST, mgr=7566, hireDate=1987-04-19 00:00:00.0, sal=3000.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7839, eName=KING, job=PRESIDENT, mgr=null, hireDate=1981-11-17 00:00:00.0, sal=5000.0, comm=null, dept=Dept [deptNo=10, dName=ACCOUNTING, loc=NEW YOR

K]]

Emp [empNo=7844, eName=TURNER, job=SALESMAN, mgr=7698, hireDate=1981-09-08 00:00:00.0, sal=1500.0, comm=0.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7876, eName=ADAMS, job=CLERK, mgr=7788, hireDate=1987-05-23 00:00:00.0, sal=1100.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7900, eName=JAMES, job=CLERK, mgr=7698, hireDate=1981-12-03 00:00:00.0, sal=950.0, comm=null, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7902, eName=FORD, job=ANALYST, mgr=7566, hireDate=1981-12-03 00:00:00.0, sal=3000.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7934, eName=MILLER, job=CLERK, mgr=7782, hireDate=1982-01-23 00:00:00.0, sal=1300.0, comm=null, dept=Dept [deptNo=10, dName=ACCOUNTING, loc=NEW YORK]

]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=67, eName=瑞士队, job=MANAGER, mgr=2018, hireDate=2018-06-21 21:37:53.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=64, dName=WorldCup, loc=Moscow]]

Emp [empNo=19, eName=韩国队, job=MANAGER, mgr=7788, hireDate=2018-06-12 00:00:00.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=13, eName=InverseT, job=TEST, mgr=7788, hireDate=2018-06-28 11:16:49.0, sal=1000.0, comm=100.0, dept=Dept [deptNo=86, dName=HBM, loc=Diego]]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=88, eName=Poly, job=Athlete, mgr=7788, hireDate=2018-06-28 10:21:47.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=90, dName=FOOTBALL, loc=Seattle]]

Emp [empNo=89, eName=Odin, job=Athlete, mgr=7788, hireDate=2018-06-28 10:21:47.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=90, dName=FOOTBALL, loc=Seattle]]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=83, eName=SET, job=主播, mgr=7788, hireDate=2018-06-28 10:08:45.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=81, dName=BigDept, loc=NEWYORK]]

Emp [empNo=87, eName=InverseF, job=TEST, mgr=7788, hireDate=2018-06-28 10:18:08.0, sal=1000.0, comm=100.0, dept=Dept [deptNo=86, dName=HBM, loc=Diego]]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=16, eName=TOM, job=CODER, mgr=7788, hireDate=2018-06-28 11:18:18.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=17, dName=VR, loc=Phoenix]]

Emp [empNo=63, eName=德国队, job=MANAGER, mgr=7788, hireDate=2018-06-21 21:24:37.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=64, dName=WorldCup, loc=Moscow]]

Hibernate:

    select

        dept0_.deptno as deptno1_0_0_,

        dept0_.dname as dname2_0_0_,

        dept0_.loc as loc3_0_0_

    from

        DEPT2 dept0_

    where

        dept0_.deptno=?

Emp [empNo=110, eName=Police, job=Police, mgr=110, hireDate=2001-09-09 09:46:40.0, sal=4000.0, comm=800.0, dept=Dept [deptNo=5, dName=DeptX, loc=null]]

inner Join输出结果

    //left join

    @Test

    public void test12(){

        Session ss=HibernateUtil.getSession();

        //根据员工名称(SCOTT)找到和他所在的部门的其他员工的信息

        //String hql="from Emp e left outer join e.dept on e.deptNo=e.dept.deptNo";//获取Emp+Dept的集合

        //String hql="select e from Emp e left outer join e.dept on e.deptNo=e.dept.deptNo";//获取Emp

        //以上两个个需要deptNo属性,在配置文件中配置property和Emp类中生成相应的getter setter

        String hql="from Emp e left outer join fetch e.dept ";//获取Emp

        Query qr=ss.createQuery(hql);

        List<Emp> el =qr.list();

        System.out.println(el.size());

        for (Emp emp : el) {

            System.out.println(emp);

        }

        HibernateUtil.closeResource(ss);

    }

left join

left join输出24条结果,因为3条是没有deptno的
Hibernate:

    select

        emp0_.empno as empno1_1_0_,

        dept1_.deptno as deptno1_0_1_,

        emp0_.ename as ename2_1_0_,

        emp0_.job as job3_1_0_,

        emp0_.mgr as mgr4_1_0_,

        emp0_.hiredate as hiredate5_1_0_,

        emp0_.sal as sal6_1_0_,

        emp0_.comm as comm7_1_0_,

        emp0_.deptno as deptno8_1_0_,

        dept1_.dname as dname2_0_1_,

        dept1_.loc as loc3_0_1_

    from

        EMP2 emp0_

    left outer join

        DEPT2 dept1_

            on emp0_.deptno=dept1_.deptno

27

Emp [empNo=7934, eName=MILLER, job=CLERK, mgr=7782, hireDate=1982-01-23 00:00:00.0, sal=1300.0, comm=null, dept=Dept [deptNo=10, dName=ACCOUNTING, loc=NEW YORK]

]

Emp [empNo=7839, eName=KING, job=PRESIDENT, mgr=null, hireDate=1981-11-17 00:00:00.0, sal=5000.0, comm=null, dept=Dept [deptNo=10, dName=ACCOUNTING, loc=NEW YOR

K]]

Emp [empNo=7782, eName=CLARK, job=MANAGER, mgr=7839, hireDate=1981-06-09 00:00:00.0, sal=2450.0, comm=null, dept=Dept [deptNo=10, dName=ACCOUNTING, loc=NEW YORK

]]

Emp [empNo=19, eName=韩国队, job=MANAGER, mgr=7788, hireDate=2018-06-12 00:00:00.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7902, eName=FORD, job=ANALYST, mgr=7566, hireDate=1981-12-03 00:00:00.0, sal=3000.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7876, eName=ADAMS, job=CLERK, mgr=7788, hireDate=1987-05-23 00:00:00.0, sal=1100.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7788, eName=SCOTT, job=ANALYST, mgr=7566, hireDate=1987-04-19 00:00:00.0, sal=3000.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7566, eName=JONES, job=MANAGER, mgr=7839, hireDate=1981-04-02 00:00:00.0, sal=2975.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7369, eName=SMITH, job=CLERK, mgr=7902, hireDate=1980-12-17 00:00:00.0, sal=800.0, comm=null, dept=Dept [deptNo=20, dName=RESEARCH, loc=DALLAS]]

Emp [empNo=7900, eName=JAMES, job=CLERK, mgr=7698, hireDate=1981-12-03 00:00:00.0, sal=950.0, comm=null, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7844, eName=TURNER, job=SALESMAN, mgr=7698, hireDate=1981-09-08 00:00:00.0, sal=1500.0, comm=0.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7698, eName=BLAKE, job=MANAGER, mgr=7839, hireDate=1981-05-01 00:00:00.0, sal=2850.0, comm=null, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7654, eName=MARTIN, job=SALESMAN, mgr=7698, hireDate=1981-09-28 00:00:00.0, sal=1250.0, comm=1400.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7521, eName=WARD, job=SALESMAN, mgr=7698, hireDate=1981-02-22 00:00:00.0, sal=1250.0, comm=500.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=7499, eName=ALLEN, job=SALESMAN, mgr=7698, hireDate=1981-02-20 00:00:00.0, sal=1600.0, comm=300.0, dept=Dept [deptNo=30, dName=SALES, loc=CHICAGO]]

Emp [empNo=110, eName=Police, job=Police, mgr=110, hireDate=2001-09-09 09:46:40.0, sal=4000.0, comm=800.0, dept=Dept [deptNo=5, dName=DeptX, loc=null]]

Emp [empNo=89, eName=Odin, job=Athlete, mgr=7788, hireDate=2018-06-28 10:21:47.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=90, dName=FOOTBALL, loc=Seattle]]

Emp [empNo=88, eName=Poly, job=Athlete, mgr=7788, hireDate=2018-06-28 10:21:47.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=90, dName=FOOTBALL, loc=Seattle]]

Emp [empNo=87, eName=InverseF, job=TEST, mgr=7788, hireDate=2018-06-28 10:18:08.0, sal=1000.0, comm=100.0, dept=Dept [deptNo=86, dName=HBM, loc=Diego]]

Emp [empNo=13, eName=InverseT, job=TEST, mgr=7788, hireDate=2018-06-28 11:16:49.0, sal=1000.0, comm=100.0, dept=Dept [deptNo=86, dName=HBM, loc=Diego]]

Emp [empNo=63, eName=德国队, job=MANAGER, mgr=7788, hireDate=2018-06-21 21:24:37.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=64, dName=WorldCup, loc=Moscow]]

Emp [empNo=67, eName=瑞士队, job=MANAGER, mgr=2018, hireDate=2018-06-21 21:37:53.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=64, dName=WorldCup, loc=Moscow]]

Emp [empNo=83, eName=SET, job=主播, mgr=7788, hireDate=2018-06-28 10:08:45.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=81, dName=BigDept, loc=NEWYORK]]

Emp [empNo=16, eName=TOM, job=CODER, mgr=7788, hireDate=2018-06-28 11:18:18.0, sal=3000.0, comm=100.0, dept=Dept [deptNo=17, dName=VR, loc=Phoenix]]

Emp [empNo=18, eName=吴奇隆, job=ACTOR, mgr=7788, hireDate=2018-06-20 00:00:00.0, sal=4000.0, comm=1000.0, dept=null]

Emp [empNo=11, eName=JASON, job=CODER, mgr=7788, hireDate=2018-06-28 11:14:47.0, sal=3000.0, comm=100.0, dept=null]

Emp [empNo=5, eName=YaoMing, job=Athlete, mgr=7788, hireDate=2018-06-28 11:08:59.0, sal=3000.0, comm=100.0, dept=null]

left join 输出结果

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