Tree Optimization

Question

Hi All!
I have a form named Chart of Accounts.
I make this form using tree patterns.
just on startup this form takes too much time to open because table of COA has 2500 records hence, it takes too much time to load.
kindly tell me the good way to resolve this problem.
i use following query to populate tree on startup:
SELECT
     1,
     LEV,
     ' ' || ACCOUNT_NO || ' -> ' || ACCOUNT_NAME,
     DECODE(IS_TRANSACTIONAL,'C','OPEN','T','NEW'),
     TO_CHAR(ACCOUNT_NO)
FROM
     ACCOUNTS_CHART
CONNECT BY
     PRIOR ACCOUNT_NO = PARENT_ACCOUNT_NO
AND      COMP_ID = :GLOBAL.COMP_ID
START WITH
     PARENT_ACCOUNT_NO IS NULL
AND      COMP_ID = :GLOBAL.COMP_ID
ORDER BY COMP_ID, ACCOUNT_NO

Answer 1

-- Specification
Package PK_Tree Is
     itTree Item := Find_Item( 'BL_TREE.IT_TREE' );
     Procedure PR_Fill_Tree;
     Procedure PR_WTNE( i_ndNode In Ftree.Node );
Procedure Pro_Release_Memory Is
End PK_Tree;
-- body
Package Body PK_Tree Is
Function Func_Add_Node( ndMaster In Ftree.Node,
                                                            ndValue In Varchar2,
                                                            ndLabel In Varchar2,
                                                            ndIcon In Varchar2 Default Null,
                                                            ndState In Number Default Ftree.Expanded_Node
                                                       ) Return Ftree.Node Is
Begin
Return Ftree.Add_Tree_Node( itTree,
                                                                      ndMaster,
                                                                      Ftree.Parent_Offset,
                                                                      Ftree.Last_Child,
                                                                      ndState,
                                                                      ndLabel,
                                                                      ndIcon,
                                                                      ndValue
End Func_Add_Node;
Procedure Pro_Query_Details( ndMaster               In Ftree.Node,
                                                                      ndMasterValue In Number
                                                                 ) Is
          Cursor crDetails Is
Select ACCOUNT_NO      Value,
               ' -> ' || ACCOUNT_NO || ' ' || ACCOUNT_NAME Label,
               Decode( IS_TRANSACTIONAL, 'C', 'OPEN', 'T', 'NEW') Icon
From ACCOUNTS_CHART
Where PARENT_ACCOUNT_NO = ndMasterValue
Order By ACCOUNT_NO;
nd Ftree.Node;
Begin
          -- show working message and set cursor state busy
          Set_Application_Property( Cursor_Style, 'BUSY' );
          Message( 'Please wiat! data is fetching...', No_Acknowledge );
          Synchronize;
For rec In crDetails Loop
-- add the node with a negative id
nd := Func_Add_Node( ndMaster, -rec.Value , rec.Label, rec.Icon );
-- don't add details here
End Loop;
          -- clear message and set cursor state normal
          Set_Application_Property( Cursor_Style, 'NORMAL' );
          Clear_Message;
End Pro_Query_Details;
Procedure PR_Fill_Tree Is
CURSOR crTop IS
SELECT ACCOUNT_NO      VALUE,
               ACCOUNT_NAME LABEL,
               Decode( IS_TRANSACTIONAL, 'C', 'OPEN', 'T', 'NEW') Icon
FROM ACCOUNTS_CHART
WHERE PARENT_ACCOUNT_NO IS NULL
ORDER BY ACCOUNT_NO;
nd Ftree.Node;
Begin
Ftree.Delete_Tree_Node( itTree, Ftree.Root_Node );
For rec In crTop Loop
-- add the node with a negative id
nd := Func_Add_Node( Ftree.Root_Node, -rec.VALUE , rec.LABEL, rec.Icon, Ftree.Collapsed_Node );
-- don't add details here
End Loop;
End PR_Fill_Tree;
Procedure PR_WTNE( i_ndNode In Ftree.Node ) Is
nValue Number;
ndDetail Ftree.Node;
Begin
-- Get the value of the node to be expanded
nValue := Ftree.Get_Tree_Node_Property( itTree, i_ndNode, Ftree.Node_Value );
If nValue < 0 Then
-- value is negative, then we have to read the details
Pro_Query_Details( i_ndNode, Abs( nValue ));
-- Now set the value of the node to positive, so that at next expansion we won't re-read the details
Ftree.Set_Tree_Node_Property( itTree, i_ndNode, Ftree.Node_Value, Abs( nValue ));
Ftree.Set_Tree_Node_Property( itTree, i_ndNode, Ftree.Node_State, Ftree.Expanded_Node );
End If;
     End PR_WTNE;
Procedure Pro_Release_Memory Is
Begin
          Ftree.Set_Tree_Node_Property( itTree, 1, Ftree.Node_State, Ftree.Collapsed_Node );
Ftree.Delete_Tree_Node( itTree, Ftree.Root_Node );
End Pro_Release_Memory;
End PK_Tree;