Useful Triggers for Oracle Developers

set_window_property(forms_mdi_window,window_state,maximize);
set_window_property('WINDOW1',window_state,maximize);
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DECLARE
A TIMER;
BEGIN
A:=CREATE_TIMER('ABC',200,REPEAT);
END;
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:DUMMY.A:= TO_CHAR(SYSDATE,'DAY   DD-MON-YYYY   HH:MI:SS AM');
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DECLARE
A NUMBER;
BEGIN
SELECT MAX(TO_NUMBER(INVNO)) INTO A FROM SHEAD
WHERE SHEAD.CCODE=:SHEAD.CCODE;
IF A IS NULL THEN
A:=1;
ELSIF A IS NOT NULL THEN
A:=A+1;
END IF;
:SHEAD.INVNO:=A;
END;
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key-next-item
DECLARE
a_value_chosen BOOLEAN;
BEGIN
a_value_chosen := Show_Lov('customer');
IF NOT a_value_chosen THEN
Message('You have not selected a value.');
Bell;
RAISE Form_Trigger_Failure;
END IF;
end;
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when-button-pressed(print)
Declare
     pl_id ParamList;
BEGIN

   Pl_Id := Get_Parameter_List('tmpdata');
   IF NOT Id_Null(Pl_Id) THEN
     Destroy_Parameter_List( pl_id );
   END IF;
    Pl_Id := Create_Parameter_List('tmpdata');
    Add_Parameter(pl_id,'P_ccode',TEXT_PARAMETER,:GLOBAL.CCODE);
    Add_Parameter(pl_id,'P_INVNO',TEXT_PARAMETER,:SHEAD.INVNO);
    Add_Parameter(pl_id,'destype',TEXT_PARAMETER,'screen');
    Run_Product(REPORTS, 'D:\AC\sale_invoice.rdf', SYNCHRONOUS, RUNTIME,FILESYSTEM,Pl_Id, NULL);
End;
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:amount:=round(nvl(:qty,0),2)*round(nvl(:price,0),2);
IF :AMOUNT >= 50000 THEN
:DISCAUNT:=5;
:TAMOUNT:=NVL(:AMOUNT,0)*5/100;
:STAX:=NVL(:AMOUNT,0)-NVL(:TAMOUNT,0);
ELSIF :AMOUNT >= 30000 THEN
:DISCAUNT:=3;
:TAMOUNT:=NVL(:AMOUNT,0)*3/100;
:STAX:=NVL(:AMOUNT,0)-NVL(:TAMOUNT,0);
ELSIF :AMOUNT >= 10000 THEN
:DISCAUNT:=1;
:TAMOUNT:=NVL(:AMOUNT,0)*1/100;
:STAX:=NVL(:AMOUNT,0)-NVL(:TAMOUNT,0);
ELSE
:DISCAUNT:=0;
:TAMOUNT:=0;
:STAX:=NVL(:AMOUNT,0)-NVL(:TAMOUNT,0);
END IF;
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