使用JDBC从存储过程中获取Oracle表类型

时间:2011-06-20 11:29:08

标签: oracle stored-procedures jdbc resultset out-parameters

我正在尝试了解使用JDBC从Oracle存储过程/函数获取表数据的不同方法。六种方式如下:

  1. 过程将模式级表类型作为OUT参数返回
  2. 过程将包级别表类型作为OUT参数返回
  3. 过程将包级别的游标类型作为OUT参数返回
  4. 函数返回模式级表类型
  5. 函数返回包级表类型
  6. 函数返回包级游标类型
  7. 以下是PL / SQL中的一些示例:

    -- schema-level table type
    CREATE TYPE t_type AS OBJECT (val VARCHAR(4));
    CREATE TYPE t_table AS TABLE OF t_type;
    
    CREATE OR REPLACE PACKAGE t_package AS
      -- package level table type
      TYPE t_table IS TABLE OF some_table%rowtype;
      -- package level cursor type
      TYPE t_cursor IS REF CURSOR;
    END library_types;
    
    -- and example procedures:
    CREATE PROCEDURE p_1 (result OUT t_table);
    CREATE PROCEDURE p_2 (result OUT t_package.t_table);
    CREATE PROCEDURE p_3 (result OUT t_package.t_cursor);
    CREATE FUNCTION f_4 RETURN t_table;
    CREATE FUNCTION f_5 RETURN t_package.t_table;
    CREATE FUNCTION f_6 RETURN t_package.t_cursor;
    

    我已成功用JDBC调用3,4和6:

    // Not OK: p_1 and p_2
    CallableStatement call = connection.prepareCall("{ call p_1(?) }");
    call.registerOutParameter(1, OracleTypes.CURSOR);
    call.execute(); // Raises PLS-00306. Obviously CURSOR is the wrong type
    
    // OK: p_3
    CallableStatement call = connection.prepareCall("{ call p_3(?) }");
    call.registerOutParameter(1, OracleTypes.CURSOR);
    call.execute();
    ResultSet rs = (ResultSet) call.getObject(1); // Cursor results
    
    // OK: f_4
    PreparedStatement stmt = connection.prepareStatement("select * from table(f_4)");
    ResultSet rs = stmt.executeQuery();
    
    // Not OK: f_5
    PreparedStatement stmt = connection.prepareStatement("select * from table(f_5)");
    stmt.executeQuery(); // Raises ORA-00902: Invalid data type
    
    // OK: f_6
    CallableStatement call = connection.prepareCall("{ ? = call f_6 }");
    call.registerOutParameter(1, OracleTypes.CURSOR);
    call.execute();
    ResultSet rs = (ResultSet) call.getObject(1); // Cursor results
    

    很明显,我无法理解

    1. 如何从存储过程中的OUT参数检索模式级和包级表类型
    2. 如何从存储的函数中检索包级别的表类型
    3. 我似乎无法找到任何关于此的文档,因为每个人总是使用游标而不是表类型。也许是因为它不可能?我更喜欢表类型,因为它们是正式定义的,可以使用字典视图(至少是模式级表类型)来发现。

      注意:显然,我可以编写一个返回OUT参数和包级表类型的包装函数。但我更喜欢干净的解决方案。

2 个答案:

答案 0 :(得分:10)

您无法从java访问PLSQL对象(案例2& 5 =包级别对象),请参阅"java - passing array in oracle stored procedure"。但是,您可以访问SQL类型(案例1和4)。

要将PL / SQL中的OUT参数传递给java,可以使用Oracle one of Tom Kyte's thread中使用OracleCallableStatement描述的方法。由于您正在检索Object表而不是VARCHAR表,因此您的代码将有一个额外的步骤。

这是一个使用SQL对象表的演示,首先是设置:

SQL> CREATE TYPE t_type AS OBJECT (val VARCHAR(4));
  2  /
Type created

SQL> CREATE TYPE t_table AS TABLE OF t_type;
  2  /
Type created

SQL> CREATE OR REPLACE PROCEDURE p_sql_type (p_out OUT t_table) IS
  2  BEGIN
  3     p_out := t_table(t_type('a'), t_type('b'));
  4  END;
  5  /
Procedure created

实际的java类(使用dbms_output.put_line进行记录,因为我将从SQL调用它,如果从java调用则使用System.out.println

SQL> CREATE OR REPLACE
  2  AND COMPILE JAVA SOURCE NAMED "ArrayDemo"
  3  as
  4  import java.sql.*;
  5  import oracle.sql.*;
  6  import oracle.jdbc.driver.*;
  7  
  8  public class ArrayDemo {
  9     
 10     private static void log(String s) throws SQLException {
 11        PreparedStatement ps =
 12           new OracleDriver().defaultConnection().prepareStatement
 13           ( "begin dbms_output.put_line(:x); end;" );
 14        ps.setString(1, s);
 15        ps.execute();
 16        ps.close();
 17     }
 18  
 19     public static void getArray() throws SQLException {
 20  
 21        Connection conn = new OracleDriver().defaultConnection();
 22  
 23        OracleCallableStatement cs =
 24           (OracleCallableStatement)conn.prepareCall
 25           ( "begin p_sql_type(?); end;" );
 26        cs.registerOutParameter(1, OracleTypes.ARRAY, "T_TABLE");
 27        cs.execute();
 28        ARRAY array_to_pass = cs.getARRAY(1);
 29  
 30        /*showing content*/
 31        Datum[] elements = array_to_pass.getOracleArray();
 32  
 33        for (int i=0;i<elements.length;i++){
 34           Object[] element = ((STRUCT) elements[i]).getAttributes();
 35           String value = (String)element[0];
 36           log("array(" + i + ").val=" + value);
 37        }
 38     }
 39  }
 40  /
Java created

我们称之为:

SQL> CREATE OR REPLACE
  2  PROCEDURE show_java_calling_plsql
  3  AS LANGUAGE JAVA
  4  NAME 'ArrayDemo.getArray()';
  5  /

Procedure created

SQL> EXEC show_java_calling_plsql;

array(0).val=a
array(1).val=b

答案 1 :(得分:0)

您还可以使用以下

public List<EmployeeBean> fetchDataFromSPForRM(String sInputDate) {

         List<EmployeeBean> employeeList = new ArrayList<EmployeeBean>();

         Connection dbCon = null;
         ResultSet data = null;
         CallableStatement cstmt = null;


         try {
                dbCon = DBUtil.getDBConnection();
                String sqlQuery = "{? = call PKG_HOLD_RELEASE.FN_RM_PDD_LIST()}";

                cstmt = dbCon.prepareCall(sqlQuery);

                cstmt.registerOutParameter(1, OracleTypes.CURSOR);

                cstmt.execute();

                data = (ResultSet) cstmt.getObject(1);              

                    while(data.next()){
                        EmployeeBean employee = new EmployeeBean();

                        employee.setEmpID(data.getString(1));
                        employee.setSubBusinessUnitId((Integer)data.getObject(2));
                        employee.setMonthOfIncentive((Integer)data.getObject(3));
                        employee.setPIPStatus(data.getString(5));
                        employee.setInvestigationStatus(data.getString(6));
                        employee.setEmpStatus(data.getString(7));
                        employee.setPortfolioPercentage((Integer)data.getObject(8));
                        employee.setIncentive((Double)data.getObject(9));
                        employee.setTotalSysemHoldAmt((Double)data.getObject(10));
                        employee.setTotalManualHoldAmt((Double)data.getObject(11));

                        employeeList.add(employee);
                    }

            } catch (SQLException e) {
                e.printStackTrace();
            }finally{
                try {

                    if(data != null){

                            data.close();               
                            data = null;
                    }
                    if(cstmt != null){

                        cstmt.close();
                        cstmt = null;
                    }
                    if(dbCon != null){

                            dbCon.close();              
                            dbCon = null;
                    }

                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }


        return employeeList;                
     }