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JPA教程 - JPA 查询Exists示例 如果子查询返回任何行#xff0c;则EXISTS条件返回true。
以下代码显示如何在JPQL中使用带有子查询的EXISTS运算符。 List l em.createQuery(SELECT e FROM Professor e WHERE EXISTS (SELECT p FROM …JPA 查询Exists示例
JPA教程 - JPA 查询Exists示例 如果子查询返回任何行则EXISTS条件返回true。
以下代码显示如何在JPQL中使用带有子查询的EXISTS运算符。 List l em.createQuery(SELECT e FROM Professor e WHERE EXISTS (SELECT p FROM Phone p WHERE p.employee e)).getResultList();以下代码显示如何使用NOT EXISTS。 List l em.createQuery(SELECT e FROM Professor e WHERE NOT EXISTS (SELECT p FROM e.phones p)).getResultList();例子
下面的代码来自PersonDaoImpl.java。
package cn.w3cschool.common;import java.util.List;import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;import org.springframework.transaction.annotation.Transactional;Transactional
public class PersonDaoImpl {public void test() {prepareData();List l em.createQuery(SELECT e FROM Professor e WHERE EXISTS (SELECT p FROM Phone p WHERE p.employee e)).getResultList();for (Object p : l) {printResult(p);}}private void prepareData() {Professor p new Professor();p.setId(0);p.setName(TOM);p.setSalary(1111L);Department d new Department();d.setId(1);d.setName(Design);p.setDepartment(d);d.getProfessors().add(p);Phone phone new Phone();phone.setId(1);phone.setNumber(111-111-1111);phone.setProfessor(p);em.persist(p);em.persist(phone);em.persist(d);}private static void printResult(Object result) {if (result null) {System.out.print(NULL);} else if (result instanceof Object[]) {Object[] row (Object[]) result;System.out.print([);for (int i 0; i row.length; i) {printResult(row[i]);}System.out.print(]);} else if (result instanceof Long || result instanceof Double|| result instanceof String) {System.out.print(result.getClass().getName() : result);} else {System.out.print(result);}System.out.println();}PersistenceContextprivate EntityManager em;
}下面的代码来自Department.java。
package cn.w3cschool.common;import java.util.HashSet;
import java.util.Set;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;Entity
public class Department {Idprivate int id;private String name;OneToMany(mappedBydepartment)private SetProfessor employees new HashSetProfessor();public int getId() {return id;}public void setId(int deptNo) {this.id deptNo;}public String getName() {return name;}public void setName(String deptName) {this.name deptName;}public SetProfessor getProfessors() {return employees;}public String toString() {return Department no: getId() , name: getName();}
}以下代码来自Address.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;Entity
public class Address {Idprivate int id;private String street;private String city;private String state;private String zip;public int getId() {return id;}public void setId(int id) {this.id id;}public String getStreet() {return street;}public void setStreet(String address) {this.street address;}public String getCity() {return city;}public void setCity(String city) {this.city city;}public String getState() {return state;}public void setState(String state) {this.state state;}public String getZip() {return zip;}public void setZip(String zip) {this.zip zip;}public String toString() {return Address id: getId() , street: getStreet() , city: getCity() , state: getState() , zip: getZip();}}以下代码来自Professor.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;Entity
public class Professor {Idprivate int id;private String name;private long salary;Temporal(TemporalType.DATE)private Date startDate;OneToOneprivate Address address;OneToMany(mappedByemployee)private CollectionPhone phones new ArrayListPhone();ManyToOneprivate Department department;ManyToOneprivate Professor manager;OneToMany(mappedBymanager)private CollectionProfessor directs new ArrayListProfessor();ManyToMany(mappedByemployees)private CollectionProject projects new ArrayListProject();public int getId() {return id;}public void setId(int empNo) {this.id empNo;}public String getName() {return name;}public void setName(String name) {this.name name;}public long getSalary() {return salary;}public void setSalary(long salary) {this.salary salary;}public Date getStartDate() {return startDate;}public void setStartDate(Date startDate) {this.startDate startDate;}public CollectionPhone getPhones() {return phones;}public void addPhone(Phone phone) {if (!getPhones().contains(phone)) {getPhones().add(phone);if (phone.getProfessor() ! null) {phone.getProfessor().getPhones().remove(phone);}phone.setProfessor(this);}}public Department getDepartment() {return department;}public void setDepartment(Department department) {if (this.department ! null) {this.department.getProfessors().remove(this);}this.department department;this.department.getProfessors().add(this);}public CollectionProfessor getDirects() {return directs;}public void addDirect(Professor employee) {if (!getDirects().contains(employee)) {getDirects().add(employee);if (employee.getManager() ! null) {employee.getManager().getDirects().remove(employee);}employee.setManager(this);}}public Professor getManager() {return manager;}public void setManager(Professor manager) {this.manager manager;}public CollectionProject getProjects() {return projects;}public void addProject(Project project) {if (!getProjects().contains(project)) {getProjects().add(project);}if (!project.getProfessors().contains(this)) {project.getProfessors().add(this);}}public Address getAddress() {return address;}public void setAddress(Address address) {this.address address; }public String toString() {return Professor getId() : name: getName() , salary: getSalary() , phones: getPhones() , managerNo: ((getManager() null) ? null : getManager().getId()) , deptNo: ((getDepartment() null) ? null : getDepartment().getId());}}以下代码来自Project.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.ManyToMany;Entity
Inheritance
public class Project {Idprotected int id;protected String name;ManyToManyprotected CollectionProfessor employees new ArrayListProfessor();public int getId() {return id;}public void setId(int projectNo) {this.id projectNo;}public String getName() {return name;}public void setName(String projectName) {this.name projectName;}public CollectionProfessor getProfessors() {return employees;}public void addProfessor(Professor employee) {if (!getProfessors().contains(employee)) {getProfessors().add(employee);}if (!employee.getProjects().contains(this)) {employee.getProjects().add(this);}}public String toString() {return getClass().getName().substring(getClass().getName().lastIndexOf(.)1) no: getId() , name: getName();}
}以下代码来自Phone.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;Entity
public class Phone {Idprivate long id;private String number;private String type;ManyToOneProfessor employee;public long getId() {return id;}public void setId(long id) {this.id id;}public String getNumber() {return number;}public void setNumber(String phoneNo) {this.number phoneNo;}public String getType() {return type;}public void setType(String phoneType) {this.type phoneType;}public Professor getProfessor() {return employee;}public void setProfessor(Professor employee) {this.employee employee;}public String toString() {return Phone id: getId() , no: getNumber() , type: getType();}
}下载 Query_Exists.zip下载 Query_Not_Exists.zip
以下是数据库转储。
Table Name: ADDRESSTable Name: DEPARTMENTRow:Column Name: ID,Column Type: INTEGER:Column Value: 1Column Name: NAME,Column Type: VARCHAR:Column Value: DesignTable Name: PHONERow:Column Name: ID,Column Type: BIGINT:Column Value: 1Column Name: NUMBER,Column Type: VARCHAR:Column Value: 111-111-1111Column Name: TYPE,Column Type: VARCHAR:Column Value: nullColumn Name: EMPLOYEE_ID,Column Type: INTEGER:Column Value: 0Table Name: PROFESSORRow:Column Name: ID,Column Type: INTEGER:Column Value: 0Column Name: NAME,Column Type: VARCHAR:Column Value: TOMColumn Name: SALARY,Column Type: BIGINT:Column Value: 1111Column Name: STARTDATE,Column Type: DATE:Column Value: nullColumn Name: ADDRESS_ID,Column Type: INTEGER:Column Value: nullColumn Name: DEPARTMENT_ID,Column Type: INTEGER:Column Value: 1Column Name: MANAGER_ID,Column Type: INTEGER:Column Value: nullTable Name: PROJECTTable Name: PROJECT_PROFESSORJPA 查询AVG简单示例
JPA教程 - JPA查询AVG简单示例 JPQL中的聚合查询的语法与SQL的语法非常相似。
有五个支持的聚合函数
AVGCOUNTMINMAXSUM
结果可以分组在GROUP BY子句中并使用HAVING子句进行过滤。
聚合JPQL查询可以使用同一查询中的许多聚合函数
SELECT d, COUNT(e), MAX(e.salary), AVG(e.salary)
FROM Department d JOIN d.employees e
GROUP BY d
HAVING COUNT(e) 5JPQL中的AVG函数计算属性的平均值。
以下行计算平均工资。
SELECT AVG(e.salary) FROM Professor e)聚合查询
聚合查询对结果进行分组并应用聚合函数以获取有关查询结果的摘要信息。
聚合查询的语法如下 SELECT select_expression
FROM from_clause
[WHERE conditional_expression]
[GROUP BY group_by_clause]
[HAVING conditional_expression]
[ORDER BY order_by_clause]例子
下面的代码来自PersonDaoImpl.java。
package cn.w3cschool.common;import java.util.List;import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;import org.springframework.transaction.annotation.Transactional;Transactional
public class PersonDaoImpl {public void test() {prepareData();List l em.createQuery(SELECT AVG(e.salary) FROM Professor e).getResultList();for (Object p : l) {printResult(p);}}private void prepareData() {Professor p new Professor();p.setId(0);p.setName(TOM);p.setSalary(1111L);Department d new Department();d.setId(1);d.setName(Design);p.setDepartment(d);d.getProfessors().add(p);Phone phone new Phone();phone.setId(1);phone.setNumber(111-111-1111);phone.setProfessor(p);em.persist(p);em.persist(phone);em.persist(d);}private static void printResult(Object result) {if (result null) {System.out.print(NULL);} else if (result instanceof Object[]) {Object[] row (Object[]) result;System.out.print([);for (int i 0; i row.length; i) {printResult(row[i]);}System.out.print(]);} else if (result instanceof Long || result instanceof Double|| result instanceof String) {System.out.print(result.getClass().getName() : result);} else {System.out.print(result);}System.out.println();}PersistenceContextprivate EntityManager em;
}以下代码来自Project.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.ManyToMany;Entity
Inheritance
public class Project {Idprotected int id;protected String name;ManyToManyprotected CollectionProfessor employees new ArrayListProfessor();public int getId() {return id;}public void setId(int projectNo) {this.id projectNo;}public String getName() {return name;}public void setName(String projectName) {this.name projectName;}public CollectionProfessor getProfessors() {return employees;}public void addProfessor(Professor employee) {if (!getProfessors().contains(employee)) {getProfessors().add(employee);}if (!employee.getProjects().contains(this)) {employee.getProjects().add(this);}}public String toString() {return getClass().getName().substring(getClass().getName().lastIndexOf(.)1) no: getId() , name: getName();}
}以下代码来自Phone.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;Entity
public class Phone {Idprivate long id;private String number;private String type;ManyToOneProfessor employee;public long getId() {return id;}public void setId(long id) {this.id id;}public String getNumber() {return number;}public void setNumber(String phoneNo) {this.number phoneNo;}public String getType() {return type;}public void setType(String phoneType) {this.type phoneType;}public Professor getProfessor() {return employee;}public void setProfessor(Professor employee) {this.employee employee;}public String toString() {return Phone id: getId() , no: getNumber() , type: getType();}
}以下代码来自Professor.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;Entity
public class Professor {Idprivate int id;private String name;private long salary;Temporal(TemporalType.DATE)private Date startDate;OneToOneprivate Address address;OneToMany(mappedByemployee)private CollectionPhone phones new ArrayListPhone();ManyToOneprivate Department department;ManyToOneprivate Professor manager;OneToMany(mappedBymanager)private CollectionProfessor directs new ArrayListProfessor();ManyToMany(mappedByemployees)private CollectionProject projects new ArrayListProject();public int getId() {return id;}public void setId(int empNo) {this.id empNo;}public String getName() {return name;}public void setName(String name) {this.name name;}public long getSalary() {return salary;}public void setSalary(long salary) {this.salary salary;}public Date getStartDate() {return startDate;}public void setStartDate(Date startDate) {this.startDate startDate;}public CollectionPhone getPhones() {return phones;}public void addPhone(Phone phone) {if (!getPhones().contains(phone)) {getPhones().add(phone);if (phone.getProfessor() ! null) {phone.getProfessor().getPhones().remove(phone);}phone.setProfessor(this);}}public Department getDepartment() {return department;}public void setDepartment(Department department) {if (this.department ! null) {this.department.getProfessors().remove(this);}this.department department;this.department.getProfessors().add(this);}public CollectionProfessor getDirects() {return directs;}public void addDirect(Professor employee) {if (!getDirects().contains(employee)) {getDirects().add(employee);if (employee.getManager() ! null) {employee.getManager().getDirects().remove(employee);}employee.setManager(this);}}public Professor getManager() {return manager;}public void setManager(Professor manager) {this.manager manager;}public CollectionProject getProjects() {return projects;}public void addProject(Project project) {if (!getProjects().contains(project)) {getProjects().add(project);}if (!project.getProfessors().contains(this)) {project.getProfessors().add(this);}}public Address getAddress() {return address;}public void setAddress(Address address) {this.address address; }public String toString() {return Professor getId() : name: getName() , salary: getSalary() , phones: getPhones() , managerNo: ((getManager() null) ? null : getManager().getId()) , deptNo: ((getDepartment() null) ? null : getDepartment().getId());}}以下代码来自Address.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;Entity
public class Address {Idprivate int id;private String street;private String city;private String state;private String zip;public int getId() {return id;}public void setId(int id) {this.id id;}public String getStreet() {return street;}public void setStreet(String address) {this.street address;}public String getCity() {return city;}public void setCity(String city) {this.city city;}public String getState() {return state;}public void setState(String state) {this.state state;}public String getZip() {return zip;}public void setZip(String zip) {this.zip zip;}public String toString() {return Address id: getId() , street: getStreet() , city: getCity() , state: getState() , zip: getZip();}}下面的代码来自Department.java。
package cn.w3cschool.common;import java.util.HashSet;
import java.util.Set;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;Entity
public class Department {Idprivate int id;private String name;OneToMany(mappedBydepartment)private SetProfessor employees new HashSetProfessor();public int getId() {return id;}public void setId(int deptNo) {this.id deptNo;}public String getName() {return name;}public void setName(String deptName) {this.name deptName;}public SetProfessor getProfessors() {return employees;}public String toString() {return Department no: getId() , name: getName();}
}下载 Query_AVG_Simple.zip
上面的代码生成以下结果。 以下是数据库转储。
Table Name: ADDRESSTable Name: DEPARTMENTRow:Column Name: ID,Column Type: INTEGER:Column Value: 1Column Name: NAME,Column Type: VARCHAR:Column Value: DesignTable Name: PHONERow:Column Name: ID,Column Type: BIGINT:Column Value: 1Column Name: NUMBER,Column Type: VARCHAR:Column Value: 111-111-1111Column Name: TYPE,Column Type: VARCHAR:Column Value: nullColumn Name: EMPLOYEE_ID,Column Type: INTEGER:Column Value: 0Table Name: PROFESSORRow:Column Name: ID,Column Type: INTEGER:Column Value: 0Column Name: NAME,Column Type: VARCHAR:Column Value: TOMColumn Name: SALARY,Column Type: BIGINT:Column Value: 1111Column Name: STARTDATE,Column Type: DATE:Column Value: nullColumn Name: ADDRESS_ID,Column Type: INTEGER:Column Value: nullColumn Name: DEPARTMENT_ID,Column Type: INTEGER:Column Value: 1Column Name: MANAGER_ID,Column Type: INTEGER:Column Value: nullTable Name: PROJECTTable Name: PROJECT_PROFESSORJPA 查询AVG连接GroupBy示例
JPA教程 - JPA查询AVG连接GroupBy示例 以下代码显示如何在JPQL中使用连接子句使用AVG。
List l em.createQuery(SELECT d.name, AVG(e.salary) FROM Department d JOIN d.employees e GROUP BY d.name).getResultList();例子
以下代码来自Address.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;Entity
public class Address {Idprivate int id;private String street;private String city;private String state;private String zip;public int getId() {return id;}public void setId(int id) {this.id id;}public String getStreet() {return street;}public void setStreet(String address) {this.street address;}public String getCity() {return city;}public void setCity(String city) {this.city city;}public String getState() {return state;}public void setState(String state) {this.state state;}public String getZip() {return zip;}public void setZip(String zip) {this.zip zip;}public String toString() {return Address id: getId() , street: getStreet() , city: getCity() , state: getState() , zip: getZip();}}下面的代码来自Department.java。
package cn.w3cschool.common;import java.util.HashSet;
import java.util.Set;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;Entity
public class Department {Idprivate int id;private String name;OneToMany(mappedBydepartment)private SetProfessor employees new HashSetProfessor();public int getId() {return id;}public void setId(int deptNo) {this.id deptNo;}public String getName() {return name;}public void setName(String deptName) {this.name deptName;}public SetProfessor getProfessors() {return employees;}public String toString() {return Department no: getId() , name: getName();}
}以下代码来自Phone.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;Entity
public class Phone {Idprivate long id;private String number;private String type;ManyToOneProfessor employee;public long getId() {return id;}public void setId(long id) {this.id id;}public String getNumber() {return number;}public void setNumber(String phoneNo) {this.number phoneNo;}public String getType() {return type;}public void setType(String phoneType) {this.type phoneType;}public Professor getProfessor() {return employee;}public void setProfessor(Professor employee) {this.employee employee;}public String toString() {return Phone id: getId() , no: getNumber() , type: getType();}
}以下代码来自Professor.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;Entity
public class Professor {Idprivate int id;private String name;private long salary;Temporal(TemporalType.DATE)private Date startDate;OneToOneprivate Address address;OneToMany(mappedByemployee)private CollectionPhone phones new ArrayListPhone();ManyToOneprivate Department department;ManyToOneprivate Professor manager;OneToMany(mappedBymanager)private CollectionProfessor directs new ArrayListProfessor();ManyToMany(mappedByemployees)private CollectionProject projects new ArrayListProject();public int getId() {return id;}public void setId(int empNo) {this.id empNo;}public String getName() {return name;}public void setName(String name) {this.name name;}public long getSalary() {return salary;}public void setSalary(long salary) {this.salary salary;}public Date getStartDate() {return startDate;}public void setStartDate(Date startDate) {this.startDate startDate;}public CollectionPhone getPhones() {return phones;}public void addPhone(Phone phone) {if (!getPhones().contains(phone)) {getPhones().add(phone);if (phone.getProfessor() ! null) {phone.getProfessor().getPhones().remove(phone);}phone.setProfessor(this);}}public Department getDepartment() {return department;}public void setDepartment(Department department) {if (this.department ! null) {this.department.getProfessors().remove(this);}this.department department;this.department.getProfessors().add(this);}public CollectionProfessor getDirects() {return directs;}public void addDirect(Professor employee) {if (!getDirects().contains(employee)) {getDirects().add(employee);if (employee.getManager() ! null) {employee.getManager().getDirects().remove(employee);}employee.setManager(this);}}public Professor getManager() {return manager;}public void setManager(Professor manager) {this.manager manager;}public CollectionProject getProjects() {return projects;}public void addProject(Project project) {if (!getProjects().contains(project)) {getProjects().add(project);}if (!project.getProfessors().contains(this)) {project.getProfessors().add(this);}}public Address getAddress() {return address;}public void setAddress(Address address) {this.address address; }public String toString() {return Professor getId() : name: getName() , salary: getSalary() , phones: getPhones() , managerNo: ((getManager() null) ? null : getManager().getId()) , deptNo: ((getDepartment() null) ? null : getDepartment().getId());}}以下代码来自Project.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.ManyToMany;Entity
Inheritance
public class Project {Idprotected int id;protected String name;ManyToManyprotected CollectionProfessor employees new ArrayListProfessor();public int getId() {return id;}public void setId(int projectNo) {this.id projectNo;}public String getName() {return name;}public void setName(String projectName) {this.name projectName;}public CollectionProfessor getProfessors() {return employees;}public void addProfessor(Professor employee) {if (!getProfessors().contains(employee)) {getProfessors().add(employee);}if (!employee.getProjects().contains(this)) {employee.getProjects().add(this);}}public String toString() {return getClass().getName().substring(getClass().getName().lastIndexOf(.)1) no: getId() , name: getName();}
}下面的代码来自PersonDaoImpl.java。
package cn.w3cschool.common;import java.util.List;import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;import org.springframework.transaction.annotation.Transactional;Transactional
public class PersonDaoImpl {public void test() {prepareData();List l em.createQuery(SELECT d.name, AVG(e.salary) FROM Department d JOIN d.employees e GROUP BY d.name).getResultList();for (Object p : l) {printResult(p);}}private void prepareData() {Address address new Address();address.setState(BC);Professor p new Professor();p.setId(0);p.setName(TOM);p.setSalary(1111L);p.setAddress(address);Department d new Department();d.setId(1);d.setName(Design);p.setDepartment(d);d.getProfessors().add(p);Phone phone new Phone();phone.setId(1);phone.setNumber(111-111-1111);phone.setProfessor(p);em.persist(p);em.persist(phone);em.persist(address);em.persist(d);}private static void printResult(Object result) {if (result null) {System.out.print(NULL);} else if (result instanceof Object[]) {Object[] row (Object[]) result;System.out.print([);for (int i 0; i row.length; i) {printResult(row[i]);}System.out.print(]);} else if (result instanceof Long || result instanceof Double|| result instanceof String) {System.out.print(result.getClass().getName() : result);} else {System.out.print(result);}System.out.println();}PersistenceContextprivate EntityManager em;
}下载 Query_AVG_Join_GroupBy.zip
上面的代码生成以下结果。 以下是数据库转储。
Table Name: ADDRESSRow:Column Name: ID,Column Type: INTEGER:Column Value: 0Column Name: CITY,Column Type: VARCHAR:Column Value: nullColumn Name: STATE,Column Type: VARCHAR:Column Value: BCColumn Name: STREET,Column Type: VARCHAR:Column Value: nullColumn Name: ZIP,Column Type: VARCHAR:Column Value: nullTable Name: DEPARTMENTRow:Column Name: ID,Column Type: INTEGER:Column Value: 1Column Name: NAME,Column Type: VARCHAR:Column Value: DesignTable Name: PHONERow:Column Name: ID,Column Type: BIGINT:Column Value: 1Column Name: NUMBER,Column Type: VARCHAR:Column Value: 111-111-1111Column Name: TYPE,Column Type: VARCHAR:Column Value: nullColumn Name: EMPLOYEE_ID,Column Type: INTEGER:Column Value: 0Table Name: PROFESSORRow:Column Name: ID,Column Type: INTEGER:Column Value: 0Column Name: NAME,Column Type: VARCHAR:Column Value: TOMColumn Name: SALARY,Column Type: BIGINT:Column Value: 1111Column Name: STARTDATE,Column Type: DATE:Column Value: nullColumn Name: ADDRESS_ID,Column Type: INTEGER:Column Value: 0Column Name: DEPARTMENT_ID,Column Type: INTEGER:Column Value: 1Column Name: MANAGER_ID,Column Type: INTEGER:Column Value: nullTable Name: PROJECTTable Name: PROJECT_PROFESSORJPA 查询COUNT示例
JPA教程 - JPA查询COUNT示例 COUNT函数用于计算表中的元素。 SELECT d.name, COUNT(e), AVG(e.salary) FROM Department d JOIN d.employees e GROUP BY d.name)例子
下面的代码来自PersonDaoImpl.java。
package cn.w3cschool.common;import java.util.List;import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;import org.springframework.transaction.annotation.Transactional;Transactional
public class PersonDaoImpl {public void test() {prepareData();List l em.createQuery(SELECT d.name, COUNT(e), AVG(e.salary) FROM Department d JOIN d.employees e GROUP BY d.name).getResultList();for (Object p : l) {printResult(p);}}private void prepareData() {Professor p new Professor();p.setId(0);p.setName(TOM);p.setSalary(1111L);Department d new Department();d.setId(1);d.setName(Design);p.setDepartment(d);d.getProfessors().add(p);Phone phone new Phone();phone.setId(1);phone.setNumber(111-111-1111);phone.setProfessor(p);em.persist(p);em.persist(phone);em.persist(d);}private static void printResult(Object result) {if (result null) {System.out.print(NULL);} else if (result instanceof Object[]) {Object[] row (Object[]) result;System.out.print([);for (int i 0; i row.length; i) {printResult(row[i]);}System.out.print(]);} else if (result instanceof Long || result instanceof Double|| result instanceof String) {System.out.print(result.getClass().getName() : result);} else {System.out.print(result);}System.out.println();}PersistenceContextprivate EntityManager em;
}以下代码来自Project.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.ManyToMany;Entity
Inheritance
public class Project {Idprotected int id;protected String name;ManyToManyprotected CollectionProfessor employees new ArrayListProfessor();public int getId() {return id;}public void setId(int projectNo) {this.id projectNo;}public String getName() {return name;}public void setName(String projectName) {this.name projectName;}public CollectionProfessor getProfessors() {return employees;}public void addProfessor(Professor employee) {if (!getProfessors().contains(employee)) {getProfessors().add(employee);}if (!employee.getProjects().contains(this)) {employee.getProjects().add(this);}}public String toString() {return getClass().getName().substring(getClass().getName().lastIndexOf(.)1) no: getId() , name: getName();}
}以下代码来自Address.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;Entity
public class Address {Idprivate int id;private String street;private String city;private String state;private String zip;public int getId() {return id;}public void setId(int id) {this.id id;}public String getStreet() {return street;}public void setStreet(String address) {this.street address;}public String getCity() {return city;}public void setCity(String city) {this.city city;}public String getState() {return state;}public void setState(String state) {this.state state;}public String getZip() {return zip;}public void setZip(String zip) {this.zip zip;}public String toString() {return Address id: getId() , street: getStreet() , city: getCity() , state: getState() , zip: getZip();}}以下代码来自Phone.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;Entity
public class Phone {Idprivate long id;private String number;private String type;ManyToOneProfessor employee;public long getId() {return id;}public void setId(long id) {this.id id;}public String getNumber() {return number;}public void setNumber(String phoneNo) {this.number phoneNo;}public String getType() {return type;}public void setType(String phoneType) {this.type phoneType;}public Professor getProfessor() {return employee;}public void setProfessor(Professor employee) {this.employee employee;}public String toString() {return Phone id: getId() , no: getNumber() , type: getType();}
}以下代码来自Professor.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;Entity
public class Professor {Idprivate int id;private String name;private long salary;Temporal(TemporalType.DATE)private Date startDate;OneToOneprivate Address address;OneToMany(mappedByemployee)private CollectionPhone phones new ArrayListPhone();ManyToOneprivate Department department;ManyToOneprivate Professor manager;OneToMany(mappedBymanager)private CollectionProfessor directs new ArrayListProfessor();ManyToMany(mappedByemployees)private CollectionProject projects new ArrayListProject();public int getId() {return id;}public void setId(int empNo) {this.id empNo;}public String getName() {return name;}public void setName(String name) {this.name name;}public long getSalary() {return salary;}public void setSalary(long salary) {this.salary salary;}public Date getStartDate() {return startDate;}public void setStartDate(Date startDate) {this.startDate startDate;}public CollectionPhone getPhones() {return phones;}public void addPhone(Phone phone) {if (!getPhones().contains(phone)) {getPhones().add(phone);if (phone.getProfessor() ! null) {phone.getProfessor().getPhones().remove(phone);}phone.setProfessor(this);}}public Department getDepartment() {return department;}public void setDepartment(Department department) {if (this.department ! null) {this.department.getProfessors().remove(this);}this.department department;this.department.getProfessors().add(this);}public CollectionProfessor getDirects() {return directs;}public void addDirect(Professor employee) {if (!getDirects().contains(employee)) {getDirects().add(employee);if (employee.getManager() ! null) {employee.getManager().getDirects().remove(employee);}employee.setManager(this);}}public Professor getManager() {return manager;}public void setManager(Professor manager) {this.manager manager;}public CollectionProject getProjects() {return projects;}public void addProject(Project project) {if (!getProjects().contains(project)) {getProjects().add(project);}if (!project.getProfessors().contains(this)) {project.getProfessors().add(this);}}public Address getAddress() {return address;}public void setAddress(Address address) {this.address address; }public String toString() {return Professor getId() : name: getName() , salary: getSalary() , phones: getPhones() , managerNo: ((getManager() null) ? null : getManager().getId()) , deptNo: ((getDepartment() null) ? null : getDepartment().getId());}}下面的代码来自Department.java。
package cn.w3cschool.common;import java.util.HashSet;
import java.util.Set;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;Entity
public class Department {Idprivate int id;private String name;OneToMany(mappedBydepartment)private SetProfessor employees new HashSetProfessor();public int getId() {return id;}public void setId(int deptNo) {this.id deptNo;}public String getName() {return name;}public void setName(String deptName) {this.name deptName;}public SetProfessor getProfessors() {return employees;}public String toString() {return Department no: getId() , name: getName();}
}下载 Query_AVG.zip
上面的代码生成以下结果。 以下是数据库转储。
Table Name: ADDRESSTable Name: DEPARTMENTRow:Column Name: ID,Column Type: INTEGER:Column Value: 1Column Name: NAME,Column Type: VARCHAR:Column Value: DesignTable Name: PHONERow:Column Name: ID,Column Type: BIGINT:Column Value: 1Column Name: NUMBER,Column Type: VARCHAR:Column Value: 111-111-1111Column Name: TYPE,Column Type: VARCHAR:Column Value: nullColumn Name: EMPLOYEE_ID,Column Type: INTEGER:Column Value: 0Table Name: PROFESSORRow:Column Name: ID,Column Type: INTEGER:Column Value: 0Column Name: NAME,Column Type: VARCHAR:Column Value: TOMColumn Name: SALARY,Column Type: BIGINT:Column Value: 1111Column Name: STARTDATE,Column Type: DATE:Column Value: nullColumn Name: ADDRESS_ID,Column Type: INTEGER:Column Value: nullColumn Name: DEPARTMENT_ID,Column Type: INTEGER:Column Value: 1Column Name: MANAGER_ID,Column Type: INTEGER:Column Value: nullTable Name: PROJECTTable Name: PROJECT_PROFESSORJPA 查询计数其中子查询示例
JPA教程 - JPA 查询计数其中子查询示例 以下代码显示如何在子查询中使用COUNT函数。
List l em.createQuery(SELECT m FROM Professor m WHERE (SELECT COUNT(e) FROM Professor e WHERE e.manager m) 0).getResultList();例子
以下代码来自Professor.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;Entity
public class Professor {Idprivate int id;private String name;private long salary;Temporal(TemporalType.DATE)private Date startDate;OneToOneprivate Address address;OneToMany(mappedByemployee)private CollectionPhone phones new ArrayListPhone();ManyToOneprivate Department department;ManyToOneprivate Professor manager;OneToMany(mappedBymanager)private CollectionProfessor directs new ArrayListProfessor();ManyToMany(mappedByemployees)private CollectionProject projects new ArrayListProject();public int getId() {return id;}public void setId(int empNo) {this.id empNo;}public String getName() {return name;}public void setName(String name) {this.name name;}public long getSalary() {return salary;}public void setSalary(long salary) {this.salary salary;}public Date getStartDate() {return startDate;}public void setStartDate(Date startDate) {this.startDate startDate;}public CollectionPhone getPhones() {return phones;}public void addPhone(Phone phone) {if (!getPhones().contains(phone)) {getPhones().add(phone);if (phone.getProfessor() ! null) {phone.getProfessor().getPhones().remove(phone);}phone.setProfessor(this);}}public Department getDepartment() {return department;}public void setDepartment(Department department) {if (this.department ! null) {this.department.getProfessors().remove(this);}this.department department;this.department.getProfessors().add(this);}public CollectionProfessor getDirects() {return directs;}public void addDirect(Professor employee) {if (!getDirects().contains(employee)) {getDirects().add(employee);if (employee.getManager() ! null) {employee.getManager().getDirects().remove(employee);}employee.setManager(this);}}public Professor getManager() {return manager;}public void setManager(Professor manager) {this.manager manager;}public CollectionProject getProjects() {return projects;}public void addProject(Project project) {if (!getProjects().contains(project)) {getProjects().add(project);}if (!project.getProfessors().contains(this)) {project.getProfessors().add(this);}}public Address getAddress() {return address;}public void setAddress(Address address) {this.address address; }public String toString() {return Professor getId() : name: getName() , salary: getSalary() , phones: getPhones() , managerNo: ((getManager() null) ? null : getManager().getId()) , deptNo: ((getDepartment() null) ? null : getDepartment().getId());}}下面的代码来自Department.java。
package cn.w3cschool.common;import java.util.HashSet;
import java.util.Set;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;Entity
public class Department {Idprivate int id;private String name;OneToMany(mappedBydepartment)private SetProfessor employees new HashSetProfessor();public int getId() {return id;}public void setId(int deptNo) {this.id deptNo;}public String getName() {return name;}public void setName(String deptName) {this.name deptName;}public SetProfessor getProfessors() {return employees;}public String toString() {return Department no: getId() , name: getName();}
}下面的代码来自PersonDaoImpl.java。
package cn.w3cschool.common;import java.util.List;import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;import org.springframework.transaction.annotation.Transactional;Transactional
public class PersonDaoImpl {public void test() {prepareData();List l em.createQuery(SELECT m FROM Professor m WHERE (SELECT COUNT(e) FROM Professor e WHERE e.manager m) 0).getResultList();for (Object p : l) {printResult(p);}}private void prepareData() {Professor p new Professor();p.setId(0);p.setName(TOM);p.setSalary(1111L);Department d new Department();d.setId(1);d.setName(Design);p.setDepartment(d);d.getProfessors().add(p);em.persist(p);em.persist(d);}private static void printResult(Object result) {if (result null) {System.out.print(NULL);} else if (result instanceof Object[]) {Object[] row (Object[]) result;System.out.print([);for (int i 0; i row.length; i) {printResult(row[i]);}System.out.print(]);} else if (result instanceof Long || result instanceof Double|| result instanceof String) {System.out.print(result.getClass().getName() : result);} else {System.out.print(result);}System.out.println();}PersistenceContextprivate EntityManager em;
}以下代码来自Project.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.ManyToMany;Entity
Inheritance
public class Project {Idprotected int id;protected String name;ManyToManyprotected CollectionProfessor employees new ArrayListProfessor();public int getId() {return id;}public void setId(int projectNo) {this.id projectNo;}public String getName() {return name;}public void setName(String projectName) {this.name projectName;}public CollectionProfessor getProfessors() {return employees;}public void addProfessor(Professor employee) {if (!getProfessors().contains(employee)) {getProfessors().add(employee);}if (!employee.getProjects().contains(this)) {employee.getProjects().add(this);}}public String toString() {return getClass().getName().substring(getClass().getName().lastIndexOf(.)1) no: getId() , name: getName();}
}以下代码来自Address.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;Entity
public class Address {Idprivate int id;private String street;private String city;private String state;private String zip;public int getId() {return id;}public void setId(int id) {this.id id;}public String getStreet() {return street;}public void setStreet(String address) {this.street address;}public String getCity() {return city;}public void setCity(String city) {this.city city;}public String getState() {return state;}public void setState(String state) {this.state state;}public String getZip() {return zip;}public void setZip(String zip) {this.zip zip;}public String toString() {return Address id: getId() , street: getStreet() , city: getCity() , state: getState() , zip: getZip();}}以下代码来自Phone.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;Entity
public class Phone {Idprivate long id;private String number;private String type;ManyToOneProfessor employee;public long getId() {return id;}public void setId(long id) {this.id id;}public String getNumber() {return number;}public void setNumber(String phoneNo) {this.number phoneNo;}public String getType() {return type;}public void setType(String phoneType) {this.type phoneType;}public Professor getProfessor() {return employee;}public void setProfessor(Professor employee) {this.employee employee;}public String toString() {return Phone id: getId() , no: getNumber() , type: getType();}
}下载 Query_Count_Where_Subquery.zip
以下是数据库转储。
Table Name: ADDRESSTable Name: DEPARTMENTRow:Column Name: ID,Column Type: INTEGER:Column Value: 1Column Name: NAME,Column Type: VARCHAR:Column Value: DesignTable Name: PHONETable Name: PROFESSORRow:Column Name: ID,Column Type: INTEGER:Column Value: 0Column Name: NAME,Column Type: VARCHAR:Column Value: TOMColumn Name: SALARY,Column Type: BIGINT:Column Value: 1111Column Name: STARTDATE,Column Type: DATE:Column Value: nullColumn Name: ADDRESS_ID,Column Type: INTEGER:Column Value: nullColumn Name: DEPARTMENT_ID,Column Type: INTEGER:Column Value: 1Column Name: MANAGER_ID,Column Type: INTEGER:Column Value: nullTable Name: PROJECTTable Name: PROJECT_PROFESSORJPA 查询函数示例
JPA教程 - JPA查询函数示例 JPQL支持的函数表达式如下所示。
函数描述ABS(number)返回number参数的无符号版本。结果类型与参数类型(整数浮点型或双精度型)相同。CONCAT(string1string2)连接string1和string2。CURRENT_DATE返回数据库服务器定义的当前日期。CURRENT_TIME从数据库服务器返回当前时间。CURRENT_TIMESTAMP返回数据库服务器的当前时间戳。INDEX(identification variable)返回有序列表中实体的位置。LENGTH(string)返回字符串参数中的字符数。LOCATE(string1string2 [start])返回string1中string1的位置可选择从start指示的位置开始。如果找不到字符串结果为零。LOWER(string)返回字符串参数的小写形式。MOD(number1number2)返回数字参数number1和number2的模数作为整数。SIZE(collection)返回集合中元素的数量如果集合为空则返回0。SQRT(number)返回数字参数的平方根作为double。SUBSTRING(string, start, end)返回输入字符串的一部分从由start开始到length字符指示的索引开始。字符串索引从一个开始。UPPER(string)返回字符串参数的大写形式。TRIM([[LEADING | TRAILING | BOTH] [char] FROM] string)删除字符串中的前导和/或尾随字符。如果不使用可选的LEADINGTRAILING或BOTH关键字则删除前导和尾随字符。默认修剪字符是空格字符。
以下代码显示如何在JPQL中使用CONCATSUBSTRING和LOCATE字符串函数。 em.createQuery(UPDATE Phone p SET p.number CONCAT(0,SUBSTRING(p.number, LOCATE(p.number, -), 4)), p.type Business ).executeUpdate();例子
以下代码来自Project.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.ManyToMany;Entity
Inheritance
public class Project {Idprotected int id;protected String name;ManyToManyprotected CollectionProfessor employees new ArrayListProfessor();public int getId() {return id;}public void setId(int projectNo) {this.id projectNo;}public String getName() {return name;}public void setName(String projectName) {this.name projectName;}public CollectionProfessor getProfessors() {return employees;}public void addProfessor(Professor employee) {if (!getProfessors().contains(employee)) {getProfessors().add(employee);}if (!employee.getProjects().contains(this)) {employee.getProjects().add(this);}}public String toString() {return getClass().getName().substring(getClass().getName().lastIndexOf(.)1) no: getId() , name: getName();}
}下面的代码来自PersonDaoImpl.java。
package cn.w3cschool.common;import java.util.List;import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;import org.springframework.transaction.annotation.Transactional;Transactional
public class PersonDaoImpl {public void test() {prepareData();em.createQuery(UPDATE Phone p SET p.number CONCAT(0,SUBSTRING(p.number, LOCATE(p.number, -), 4)), p.type Business ).executeUpdate();}private void prepareData() {Professor p new Professor();p.setId(0);p.setName(TOM);p.setSalary(1111L);Department d new Department();d.setId(1);d.setName(Design);p.setDepartment(d);d.getProfessors().add(p);Phone phone new Phone();phone.setId(1);phone.setNumber(111-111-1111);phone.setProfessor(p);em.persist(p);em.persist(phone);em.persist(d);}private static void printResult(Object result) {if (result null) {System.out.print(NULL);} else if (result instanceof Object[]) {Object[] row (Object[]) result;System.out.print([);for (int i 0; i row.length; i) {printResult(row[i]);}System.out.print(]);} else if (result instanceof Long || result instanceof Double|| result instanceof String) {System.out.print(result.getClass().getName() : result);} else {System.out.print(result);}System.out.println();}PersistenceContextprivate EntityManager em;
}以下代码来自Phone.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToOne;Entity
public class Phone {Idprivate long id;private String number;private String type;ManyToOneProfessor employee;public long getId() {return id;}public void setId(long id) {this.id id;}public String getNumber() {return number;}public void setNumber(String phoneNo) {this.number phoneNo;}public String getType() {return type;}public void setType(String phoneType) {this.type phoneType;}public Professor getProfessor() {return employee;}public void setProfessor(Professor employee) {this.employee employee;}public String toString() {return Phone id: getId() , no: getNumber() , type: getType();}
}以下代码来自Professor.java。
package cn.w3cschool.common;import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.ManyToMany;
import javax.persistence.ManyToOne;
import javax.persistence.OneToMany;
import javax.persistence.OneToOne;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;Entity
public class Professor {Idprivate int id;private String name;private long salary;Temporal(TemporalType.DATE)private Date startDate;OneToOneprivate Address address;OneToMany(mappedByemployee)private CollectionPhone phones new ArrayListPhone();ManyToOneprivate Department department;ManyToOneprivate Professor manager;OneToMany(mappedBymanager)private CollectionProfessor directs new ArrayListProfessor();ManyToMany(mappedByemployees)private CollectionProject projects new ArrayListProject();public int getId() {return id;}public void setId(int empNo) {this.id empNo;}public String getName() {return name;}public void setName(String name) {this.name name;}public long getSalary() {return salary;}public void setSalary(long salary) {this.salary salary;}public Date getStartDate() {return startDate;}public void setStartDate(Date startDate) {this.startDate startDate;}public CollectionPhone getPhones() {return phones;}public void addPhone(Phone phone) {if (!getPhones().contains(phone)) {getPhones().add(phone);if (phone.getProfessor() ! null) {phone.getProfessor().getPhones().remove(phone);}phone.setProfessor(this);}}public Department getDepartment() {return department;}public void setDepartment(Department department) {if (this.department ! null) {this.department.getProfessors().remove(this);}this.department department;this.department.getProfessors().add(this);}public CollectionProfessor getDirects() {return directs;}public void addDirect(Professor employee) {if (!getDirects().contains(employee)) {getDirects().add(employee);if (employee.getManager() ! null) {employee.getManager().getDirects().remove(employee);}employee.setManager(this);}}public Professor getManager() {return manager;}public void setManager(Professor manager) {this.manager manager;}public CollectionProject getProjects() {return projects;}public void addProject(Project project) {if (!getProjects().contains(project)) {getProjects().add(project);}if (!project.getProfessors().contains(this)) {project.getProfessors().add(this);}}public Address getAddress() {return address;}public void setAddress(Address address) {this.address address; }public String toString() {return Professor getId() : name: getName() , salary: getSalary() , phones: getPhones() , managerNo: ((getManager() null) ? null : getManager().getId()) , deptNo: ((getDepartment() null) ? null : getDepartment().getId());}}以下代码来自Address.java。
package cn.w3cschool.common;import javax.persistence.Entity;
import javax.persistence.Id;Entity
public class Address {Idprivate int id;private String street;private String city;private String state;private String zip;public int getId() {return id;}public void setId(int id) {this.id id;}public String getStreet() {return street;}public void setStreet(String address) {this.street address;}public String getCity() {return city;}public void setCity(String city) {this.city city;}public String getState() {return state;}public void setState(String state) {this.state state;}public String getZip() {return zip;}public void setZip(String zip) {this.zip zip;}public String toString() {return Address id: getId() , street: getStreet() , city: getCity() , state: getState() , zip: getZip();}}下面的代码来自Department.java。
package cn.w3cschool.common;import java.util.HashSet;
import java.util.Set;import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;Entity
public class Department {Idprivate int id;private String name;OneToMany(mappedBydepartment)private SetProfessor employees new HashSetProfessor();public int getId() {return id;}public void setId(int deptNo) {this.id deptNo;}public String getName() {return name;}public void setName(String deptName) {this.name deptName;}public SetProfessor getProfessors() {return employees;}public String toString() {return Department no: getId() , name: getName();}
}下载 Query_Substring.zip
以下是数据库转储。
Table Name: ADDRESSTable Name: DEPARTMENTRow:Column Name: ID,Column Type: INTEGER:Column Value: 1Column Name: NAME,Column Type: VARCHAR:Column Value: DesignTable Name: PHONERow:Column Name: ID,Column Type: BIGINT:Column Value: 1Column Name: NUMBER,Column Type: VARCHAR:Column Value: 0111Column Name: TYPE,Column Type: VARCHAR:Column Value: BusinessColumn Name: EMPLOYEE_ID,Column Type: INTEGER:Column Value: 0Table Name: PROFESSORRow:Column Name: ID,Column Type: INTEGER:Column Value: 0Column Name: NAME,Column Type: VARCHAR:Column Value: TOMColumn Name: SALARY,Column Type: BIGINT:Column Value: 1111Column Name: STARTDATE,Column Type: DATE:Column Value: nullColumn Name: ADDRESS_ID,Column Type: INTEGER:Column Value: nullColumn Name: DEPARTMENT_ID,Column Type: INTEGER:Column Value: 1Column Name: MANAGER_ID,Column Type: INTEGER:Column Value: nullTable Name: PROJECTTable Name: PROJECT_PROFESSOR
