18
votes

I'm trying to understand different ways of getting table data from Oracle stored procedures / functions using JDBC. The six ways are the following ones:

  1. procedure returning a schema-level table type as an OUT parameter
  2. procedure returning a package-level table type as an OUT parameter
  3. procedure returning a package-level cursor type as an OUT parameter
  4. function returning a schema-level table type
  5. function returning a package-level table type
  6. function returning a package-level cursor type

Here are some examples in PL/SQL:

-- 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;

I have succeeded in calling 3, 4, and 6 with JDBC:

// 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

So obviously, I'm having trouble understanding

  1. How to retrieve schema-level and package-level table types from OUT parameters in stored procedures
  2. How to retrieve package-level table types from stored functions

I can't seem to find any documentation on this, as everyone always uses cursors instead of table types. Maybe because it's not possible? I prefer table types, though, because they are formally defined and can be discovered using the dictionary views (at least the schema-level table types).

Note: obviously, I could write a wrapper function returning the OUT parameters and package-level table types. But I'd prefer the clean solution.

2
Are you expecting the result to be the structure of the table i.e. column1 varchar2 (100), column2 varchar2 (50)...? or do you want to see 'IS REF CURSOR' or something to that effect? - Joel Slowik
The more information about the cursor/table type I get, the better. But in any case, I think with JDBC's ResultSet.getMetaData() I can discover this information on-the-fly - Lukas Eder
@LukasEder How about mysql? I need to call a procedure in java using jdbc which returns a table... is it possible through jdbc using mysql? - Sarah Akhavan
@Jack-in-the-box: Please ask a new question. This one here is a very specific Oracle related question - Lukas Eder
@LukasEder Thank you. I asked it the other day :) here - Sarah Akhavan

2 Answers

11
votes

You can't access PLSQL objects (cases 2 & 5 = package-level objects) from java, see "java - passing array in oracle stored procedure". You can however access SQL types (case 1 and 4).

To get OUT parameters from PL/SQL to java, you can use the method described in one of Tom Kyte's thread using OracleCallableStatement. Your code will have an additional step since you're retrieving a table of Object instead of a table of VARCHAR.

Here's a demo using Table of SQL Object, first the setup:

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

The actual java class (using dbms_output.put_line to log because I will call it from SQL, use System.out.println if called from java):

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

Let's call it:

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
0
votes

You Can Also Use the below one

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;                
     }