Multiple Filter on reports

Question

All i would like to know the best way to be able to do mulitple filters on SQL generated reports i have something that looks like
select * from
from table
where endate = (select to_char(trunc(sysdate)-1, 'MM/DD/YYYY') from dual)
OR
(CLIENTNAME = :P1_XSHOWCLIENTLIST and ENDATE =:P1_XSHOWENDATE) OR
(CLIENTNAME = :P1_XSHOWCLIENTLIST)OR
(ENDATE =:P1_XSHOWENDATE) But when i select a clientname form the drop downlist which is P1_XSHOWCLIENTLIST and then select a date from the dropdown P1_XSHOWendate and do a search it does not seem to show up the results correctly.

Answer 1

So i did try the following from Johns suggestion, and i got this
I am using htmldb 2.0 and with SQL query (PL/SQL function body returning sql query
Code
declare
  q varchar2(4000);
begin
v_sql := 'select "FIXID","CLIENTNAME","CLIENTORDERID","CLIENTLOTS","ORDERPRICE","CLIENTTRADERID","BUY_SELL","CONTRACT",
"ORDERTYPE","ACTION","ORDERRECETIME","CLIENTRECAPPIATIMESTAMP","LOTSFILLED","FILLPRICE","EXCHANGEACTION","EXCHANGE","TOTALROUNDTRIP","TOTALROUNDTRIPSECS"
from  "FASTFIX_CUSTOMER_PERF" where';
if v('P1_XSHOWCLIENTLIST') IS NOT NULL then
  v_sql := v_sql || ' and CLIENTNAME = v('P1_XSHOWCLIENTLIST')'
end if;
if ('P1_XSHOWENDATE') IS NOT NULL then
  v_sql := v_sql || ' and ENDATE = v('P1_XSHOWENDATE')'
end if;
return v_sql;Error
1 error has occurred
Function returning SQL query: Query cannot be parsed within the Builder. If you believe your query is syntactically correct, check the generic columns checkbox below the region source to proceed without parsing.
(ORA-06550: line 8, column 43: PLS-00103: Encountered the symbol "P1_XSHOWCLIENTLIST" when expecting one of the following: . ( * @ % & = - + ; < / > at in is mod remainder not rem <> or != or ~= >= <= <> and or like between || member SUBMULTISET_)