如何使用Hibernate（EntityManager）或JPA 2调用Oracle函数或过程 [英] How to call Oracle Function or Procedure using Hibernate (EntityManager) or JPA 2

问题描述

我有一个返回sys-refcursor的Oracle函数，当我使用Hibernate 4调用这个函数时，我得到以下异常。

  Hibernate：{？ = call my_function（？）} 
 org.hibernate.exception.GenericJDBCException：无法执行查询
 javax.persistence.PersistenceException：org.hibernate.exception.GenericJDBCException：无法执行查询
 at org.hibernate.ejb.AbstractEntityManagerImpl.convert（AbstractEntityManagerImpl.java:1360）
位于org.hibernate.ejb.AbstractEntityManagerImpl.convert（AbstractEntityManagerImpl.java:1288）
位于org.hibernate.ejb.QueryImpl。 getSingleResult（QueryImpl.java:313）
  

如何解决此问题？

Oracle函数

 创建或替换
 FUNCTION my_function （p_val IN varchar2）
 RETURN SYS_REFCURSOR 
 AS 
 my_cursor SYS_REFCURSOR; 
 BEGIN 
 OPEN my_cursor FOR SELECT emp_name FROM employees 
 WHERE lower（emp_name）like lower（p_val ||'％'）; 
 RETURN my_cursor; 
 END; 
  

我的实体班

  @Entity 
 @ javax.persistence.NamedNativeQuery（name =getFunc，query = 
{？= call my_function（：empName）} ，
 resultClass = Employee.class，hints = 
 {@ javax.persistence.QueryHint（name =org.hibernate.callable，value =true）}）
 @Table name =EMPLOYEES）
  

和DAO

  @Override 
 public void findEmployees（QueryData data，
 String empName）{
 
列表查询=（List）entityManager.createNamedQuery（getFunc）
 .setParameter（empName，empName）
 .getSingleResult（）; 
 data.setResult（query）; 
 
  

解决方案

Oracle函数或存储过程可以使用EntityManager以下面的方式调用。

对于Oracle函数

用sys_refcursor创建一个函数作为返回类型

pre $ CREATE OR REPLACE FUNCTION my_function $ b $（p_val IN varchar2）
RETURN SYS_REFCURSOR
AS
my_cursor SYS_REFCURSOR;
BEGIN
OPEN my_cursor FOR SELECT emp_name FROM employees
WHERE lower（emp_name）like lower（p_val ||'％'）;
RETURN my_cursor;
END;

在Entity类中，将函数定义为

  @ javax.persistence.NamedNativeQuery（name =getFunc，query ={？= call $ b $ my_function（：empName）}，resultClass = Employee.class，hints = {
 @ javax.persistence.QueryHint（name =org.hibernate.callable，value =true）}）
  

用于Oracle存储过程
$ b 用 sys_refcursor 作为第一个OUT参数

  CREATE OR REPLACE PROCEDURE myProcedure（p_cursor out sys_refcursor，
 p_val in varchar2 
）
 AS 
 BEGIN 
 OPEN o_cursor FOR 
 SELECT emp_name 
 FROM employees 
 WHERE LOWER（emp_name）LIKE lower（p_val ||'％'） ; 
  

在实体类中定义过程为

<$ p $ name =getProc，query ={call
my_procedure（？，：empName）}，resultClass = Employee.class，hints = {$ p code> @ javax.persistence.NamedNativeQuery
@ javax.persistence.QueryHint（name =org.hibernate.callable，value =true）}）


，最后在DAO类的调用函数或过程中作为

  Query query = entityManager.createNamedQuery（ getFunc）; // if procedure then getProc 
 query.setParameter（empName，smith）; 
 query.getResultList（）; 
  

谢谢

I have an Oracle function which return sys-refcursor and when I call this function using Hibernate 4, I am getting the following exception.

Hibernate: { ? = call my_function(?) }
 org.hibernate.exception.GenericJDBCException: could not execute query
javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: could not execute query
    at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1360)
    at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1288)
    at org.hibernate.ejb.QueryImpl.getSingleResult(QueryImpl.java:313)

How can I resolve this?

Oracle function

create or replace 
FUNCTION my_function(p_val IN varchar2)
    RETURN SYS_REFCURSOR
  AS
    my_cursor SYS_REFCURSOR;
  BEGIN
    OPEN my_cursor FOR SELECT emp_name FROM employees
    WHERE lower(emp_name) like lower(p_val||'%');
    RETURN my_cursor;    
  END;

My Entity class

@Entity
@javax.persistence.NamedNativeQuery(name = "getFunc", query = 
"{ ? = call my_function(:empName) }", 
 resultClass = Employee.class, hints = 
 { @javax.persistence.QueryHint(name = "org.hibernate.callable", value = "true") })
 @Table(name = "EMPLOYEES")

and in DAO

    @Override
        public void findEmployees(QueryData data,
                String empName) {

        List query = (List) entityManager.createNamedQuery("getFunc")
                         .setParameter("empName", empName)
                         .getSingleResult();
                data.setResult(query);
}

解决方案

Oracle function or a stored procedure can be called using EntityManager in the following manner.

For Oracle Function

Create a function with sys_refcursor as return type

CREATE OR REPLACE FUNCTION my_function
(p_val IN varchar2)
    RETURN SYS_REFCURSOR
  AS
    my_cursor SYS_REFCURSOR;
  BEGIN
    OPEN my_cursor FOR SELECT emp_name FROM employees
    WHERE lower(emp_name) like lower(p_val||'%');
    RETURN my_cursor;    
  END;

In Entity class, define function as

@javax.persistence.NamedNativeQuery(name = "getFunc", query = "{? =  call
my_function(:empName) }", resultClass = Employee.class, hints = {
@javax.persistence.QueryHint(name = "org.hibernate.callable", value = "true") })

For Oracle Stored Procedure

Create procedure with sys_refcursor as first OUT parameter

CREATE OR REPLACE PROCEDURE myProcedure(p_cursor out sys_refcursor,
     p_val  in varchar2
)
 AS
BEGIN
     OPEN o_cursor FOR
          SELECT     emp_name 
             FROM     employees 
            WHERE     LOWER (emp_name) LIKE lower(p_val||'%');

In Entity class define procedure as

@javax.persistence.NamedNativeQuery(name = "getProc", query = "{ call
my_procedure(?,:empName) }", resultClass = Employee.class, hints = {
@javax.persistence.QueryHint(name = "org.hibernate.callable", value = "true") })

and finally in DAO class call function or procedure as

Query query = entityManager.createNamedQuery("getFunc"); // if procedure then getProc 
query.setParameter("empName","smith"); 
query.getResultList(); 

Thanks

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