Returning a list based on parameters : Function Return « Function Procedure Packages « Oracle PL/SQL Tutorial






SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL,
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /

Table created.

SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ('01','Jason',    'Martin',  to_date('19960725','YYYYMMDD'), to_date('20060725','YYYYMMDD'), 1234.56, 'Toronto',  'Programmer')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values('02','Alison',   'Mathews', to_date('19760321','YYYYMMDD'), to_date('19860221','YYYYMMDD'), 6661.78, 'Vancouver','Tester')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values('03','James',    'Smith',   to_date('19781212','YYYYMMDD'), to_date('19900315','YYYYMMDD'), 6544.78, 'Vancouver','Tester')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values('04','Celia',    'Rice',    to_date('19821024','YYYYMMDD'), to_date('19990421','YYYYMMDD'), 2344.78, 'Vancouver','Manager')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values('05','Robert',   'Black',   to_date('19840115','YYYYMMDD'), to_date('19980808','YYYYMMDD'), 2334.78, 'Vancouver','Tester')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values('06','Linda',    'Green',   to_date('19870730','YYYYMMDD'), to_date('19960104','YYYYMMDD'), 4322.78,'New York',  'Tester')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values('07','David',    'Larry',   to_date('19901231','YYYYMMDD'), to_date('19980212','YYYYMMDD'), 7897.78,'New York',  'Manager')
  3  /

1 row created.

SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values('08','James',    'Cat',     to_date('19960917','YYYYMMDD'), to_date('20020415','YYYYMMDD'), 1232.78,'Vancouver', 'Tester')
  3  /

1 row created.

SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /

ID   FIRST_NAME           LAST_NAME            START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- -------------------- -------------------- --------- --------- ---------- ---------- ---------------
01   Jason                Martin               25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison               Mathews              21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James                Smith                12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia                Rice                 24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert               Black                15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda                Green                30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David                Larry                31-DEC-90 12-FEB-98    7897.78 New York   Manager
08   James                Cat                  17-SEP-96 15-APR-02    1232.78 Vancouver  Tester

8 rows selected.

SQL>
SQL>
SQL>
SQL> create or replace type emp2_oty is object (empNo NUMBER,eName VARCHAR2(10))
  2  /


SQL>
SQL> create or replace type emp2_nt is table of emp2_oty
  2  /

Type created.

SQL>
SQL> create or replace function f_getEmps_nt(i_deptNo number, i_hireDate DATE)
  2  return emp2_nt
  3  is
  4      v_emp2_nt emp2_nt:=emp2_nt();
  5      cursor c_emp is select * from employee;
  6  begin
  7    for r_emp in c_emp
  8    loop
  9      if i_deptNo is null then
 10        if i_hireDate is null or to_char(i_hireDate,'mm')= to_char(r_emp.start_Date,'mm')
 11        then
 12           v_emp2_nt.extend;
 13           v_emp2_nt(v_emp2_nt.last):= emp2_oty(r_emp.id, r_emp.first_Name);
 14        end if;
 15      elsif i_deptNo=r_emp.id then
 16        v_emp2_nt.extend;
 17        v_emp2_nt(v_emp2_nt.last):= emp2_oty(r_emp.id, r_emp.first_name);
 18      end if;
 19    end loop;
 20    return v_emp2_nt;
 21  end;
 22  /

Function created.

SQL>
SQL> declare
  2      v_temp_nt emp2_nt;
  3  begin
  4      v_temp_nt:=f_getEmps_nt(20,null);
  5      DBMS_OUTPUT.put_line('Received:'||v_temp_nt.count);
  6
  7      v_temp_nt:=f_getEmps_nt(null,sysdate);
  8      DBMS_OUTPUT.put_line('Received:'||v_temp_nt.count);
  9
 10      v_temp_nt:=f_getEmps_nt(null,null);
 11      DBMS_OUTPUT.put_line('Received:'||v_temp_nt.count);
 12  end;
 13  /
Received:0
Received:0
Received:8

PL/SQL procedure successfully completed.

SQL>
SQL> --Or
SQL>
SQL> select F_GETEMPS_NT (10,null) from dual
  2  /

F_GETEMPS_NT(10,NULL)(EMPNO, ENAME)
----------------------------------------
EMP2_NT()

SQL>
SQL> drop type emp2_nt;

Type dropped.

SQL>
SQL> drop type emp2_oty;

Type dropped.

SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /

Table dropped.








27.3.Function Return
27.3.1.Return Types
27.3.2.Returning values with functions
27.3.3.Return number from a function
27.3.4.Return value from a function
27.3.5.Multiple RETURN Statements
27.3.6.Returning a list based on parameters
27.3.7.Return date value from a function
27.3.8.A pipelined Table Function that returns a PL/SQL type
27.3.9.Return column type
27.3.10.Statements after Return will not be executed
27.3.11.create a function to return a employee record. accept employee numner return all fields.
27.3.12.Return a table collection
27.3.13.Demonstrate returning a record.
27.3.14.Return cursor from function
27.3.15.Return user-defined type