Default where clause

Question

i am passing dynamic where clause to a detail block from the main control block by pressing a button, the problem is different types of criterias are not comming together, like i may choose any value of machine or if its null it should bring all the machines combined with status which can be either opened,closed,inspected and i added them as elements of list and if the selected item has status with value All  it shoud bring all the status for all the machines.but the problem is its not satisfying the criteria properly and when i choose all nothing is displayed in the detail block.
{code}
declare
cnt number;
var varchar2(32000);
VAAL VARCHAR2(32500);
begin
cnt := Get_List_Element_Count('IP_REP_INFO.T_LIST_IN');
if cnt >= 1
then
var := null;
for i in 1..cnt loop
  var := var||','||''''||Get_List_Element_Value('IP_REP_INFO.T_LIST_IN',i)||'''';
end loop;
Set_Block_Property('OV_JOB_MAINT', DEFAULT_WHERE,
    'WHERE (1=1 AND JOB_MACH IS NULL) OR (1=0 OR JOB_MACH in ('||substr(var, 2)||'))  AND (1 = 1 and :ORDER_STATUS IN ('||'''ALL'''||') AND
   STATUS IN (''OPENED'',''CLOSED'',''INSPECTION'') ) or ( 1=0 OR STATUS = :ORDER_STATUS)');
GO_BLOCK('OV_JOB_MAINT');
EXECUTE_QUERY;
GO_ITEM('JOB_DT');
end;
{\code}

Answer 1

First, when setting the DEFAULT_WHERE property of a block, I like to assign the dynamic where clause to a variable so I can output it to the screen or look at the value through the Forms Debugger to ensure it is formatted correctly.
Second, have you perfected your WHERE clause in SQLPlus or SQL Developer to ensure it is returning exaclty what you want?  To me, this is a critical first step that should be completed first before trying to create the dynamic where clause through code.
Third, it is not necessary to include the 'WHERE' keyword in your code because Forms will automatically do this for you.  Will it work?  Yes, but your query ends up looking like this when Forms executes the query.
SELECT {...list of your columns here...}
WHERE ( WHERE 'Your Dynamic Where Clause' )
See my comments in your code sample...
Set_Block_Property('OV_JOB_MAINT', DEFAULT_WHERE,
    'WHERE (1=1 -- This is not needed, just evaluate JOB_MACH IS NULL
     AND JOB_MACH IS NULL)
      OR (1=0 -- I don't understand why you want a FALSE test here...
          OR JOB_MACH in ('||substr(var, 2)||')
             -- Have you outputted the value of VAR to the screen to ensure
             -- it is formatted correctly?
     AND (1 = 1 -- Again, this is not needed
          and :ORDER_STATUS IN ('||'''ALL'''||')
     AND STATUS IN (''OPENED'',''CLOSED'',''INSPECTION'') )
      or ( 1=0 -- Again, why do you need a FALSE test here?
           OR STATUS = :ORDER_STATUS)'
Regarding...
if the selected item has status with value All  it shoud bring all the status for all the machines.but the problem is its not satisfying the criteria properly and when i choose all nothing is displayed in the detail block.
Do you have an Order Status with the value of "ALL" in your table?
My guess is that you don't because each record would have to record its actual status as well as the ALL status.  Based on this assumption, I recommend you alter your SQL so that it looks for the actual status as well as perform an IN comparison.
  'AND status IN ('||DECODE(:ORDER_STATUS,'ALL','''OPENED'',''CLOSED'',''INSPECTION'' ',''''||:ORDER_STATUS)||''')'
The addition of the DECODE enables you to query on all statuses when the :ORDER_STATUS = ALL or it returns the status listed in the :ORDER_STATUS field.
Hope this helps.
Craig...