Oracle Procedure update

Question

We have two tables.
1. EMP_STAGE 2. EMP
Find the structure for the above two tables.
EMP_STAGE                                                       EMP
EMP_ID                                                                 ID
PAN                                                                       EMP_PAN
STATUS                                                                STATUS
LAST_DAY                                                            EMP_FLAG
                                                                              END_DATE
one of our applications EMP_STAGE table get the data then EMP_STAGE table data will be loaded into EMP table.
I need to write a procedure, based on the results of EMP_STAGE table EMPLOYEE table should update like ,
1. if employee is still with the organization the STATUS is "Active" in EMP_STAGE table if he resigned or terminated then his status should be "inactive"  and  LAST_DAY (date format) of employees data also updated in EMP_STAG table.
2. while loading the data into EMP table based on the data from EMP_STAGE , in employee table STATUS of employee ='ACTIVE/INACTIVE' and END_DATE = LAST_DAY( from EMP_STAGE table) based on these two the column EMP_FLAG will update like  EMP_FLAG = ( if employee existed then 'YES' else 'NO') ;
please provide me your thoughts on this.

Answer 1

now i am confused going back to your previous posting you do not have those end_dates on your sample data. below is your sample data.
emp_stage.EMPID emp_stage.LAST_DAY emp_stage.STATUS Status Match? emp.ID  emp.END_DATE emp.STATUS
1012028         19-Jun-13          T                FALSE         1012028 19-Jun-13    A
1472711         20-Jun-13          T                FALSE         1472711 20-Jun-13    A
1012025         21-Jun-13          T                FALSE         1012025 21-Jun-13    A
234567          19-Jun-13          T                FALSE         234567  19-Jun-13    A
43567           20-Jun-13          T                FALSE         43567   20-Jun-13
76788           21-Jun-13          T                FALSE         76788   21-Jun-13    A
1234876         22-Jun-13          T                FALSE         1234876 22-Jun-13    A
maybe it will help if you can re-post again wtih a clean sample data for example.
source emp_stage table:
emp_id     pan        status    last_day
1012028               Inactive  19-Jun-13
1472711               Inactive  20-Jun-13
1234567               Active    29-Dec-13
expected result in emp table:
id         emp_pan    status    emp_flag   end_date
1012028               T         N          19-Jun-13
1472711               T         N          20-Jun-13
1234567               A         Y          29-Dec-13
you can give this a try:
with emp_stage as
(select 1012028 emp_id, to_date('19-Jun-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 1472711 emp_id, to_date('20-Jun-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 1012025 emp_id, to_date('21-Jun-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 234567  emp_id, to_date('19-Jun-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 43567   emp_id, to_date('20-Jun-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 76788   emp_id, to_date('21-Jun-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 1234876 emp_id, to_date('22-Jun-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 54321   emp_id, to_date('29-Dec-13','dd-mon-rr') last_day, 'Active' status from dual union all
select 67890   emp_id, to_date('30-Aug-13','dd-mon-rr') last_day, 'Active' status from dual)
select emp_id,
       case when status = 'ACTIVE' or (trunc(last_day) > trunc(sysdate)) then
             'A'
            when status = 'INACTIVE' or (trunc(last_day) < trunc(sysdate)) then
             'T'
       end status,
       case when status = 'ACTIVE' or (trunc(last_day) > trunc(sysdate)) then
             'N'
            when status = 'INACTIVE' or (trunc(last_day) < trunc(sysdate)) then
             'Y'
       end emp_flag,
       last_day
  from EMP_STAGE;
    EMP_ID STATUS EMP_FLAG LAST_DAY
   1012028 T      Y        19-Jun-2013
   1472711 T      Y        20-Jun-2013
   1012025 T      Y        21-Jun-2013
    234567 T      Y        19-Jun-2013
     43567 T      Y        20-Jun-2013
     76788 T      Y        21-Jun-2013
   1234876 T      Y        22-Jun-2013
     54321 A      N        29-Dec-2013
     67890 A      N        30-Aug-2013
9 rows selected
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