Different order of subgroups groups per configuration in order by clause

Question

Hello,
I have a question regarding Order by and group by of SQL. I have three tables, Groupconfig and ItemConfig and Items.
Group has a extra field which will specify the sorting order of the items when read out from the database.
I have the choice of Sorting by alpa description of the item or a sorting order defined on the item table.
But when I write some SQL to retrieve all the items in the items table and join to the item config table, to get the description of the item and the sorting number,
then join again to the groupconfig table to get the sorting of each group.
Problem is that when I run the query the data is not quite returned in the correct order in each group as defined in the group config for each group.
I know there are differences with the NLS_SORT variable in Oracle but I have a feeling that this is more to do with my SQL can someone help?
I require the overall groups to be retuned by group ID, and within each group a different ordering.
SELECT * FROM
SELECT
GC.GROUPID GP_GROUPID,
GC.DESCRIP GP_DESCRIP,
GC.SORTING_ORDER GP_SORTINGORDER,
IC.SORTING_ORDER IC_SORDER,
IC.DESCR IC_DESCRIPTION,
IC.ITEMID IC_ITEMID,
RID.UNIT I_UNIT,
IC.SORTING_ORDER
FROM
RF_ITEMDETAILS RID,
RF_ITEMCONFIG IC,
RF_GROUPCONFIG GC
WHERE
IC.ITEMID = RID.ITEMID
AND GC.GROUPID = IC.GROUPID
ORDER BY
CASE WHEN GC.SORTING_TYPE = 'N' THEN IC.SORTING_ORDER END,
CASE WHEN GC.SORTING_TYPE = 'A' THEN IC.DESCR END
) GP
ORDER BY GP.GP_SORTINGORDER
But when I run this second group is correct and ordered by Numeric sorting but the first group by the sorting number field is never correct.
Doe this SQL look correct or does anyone know if a good performat way to do this?

Answer 1

maaher cant beleive I actually asked that question. thanks for your reply.
I have changed my SQL to build up the Orber by clause using the case statements like so....( and added Product Group table in also!)
SELECT
PC.PRODUCTID PC_ID,
PC.DESCR PC_DESC,
PC.SORTING_ORDER PC_SORT,
GC.GROUPID GC_GROUPID,
GC.DESCRIP GC_DESCRIP,
GC.SORTING_ORDER GC_SORTINGORDER,
IC.ITEMID IC_ITEMID,
IC.DESCR IC_DESCRIPTION,
IC.SORTING_ORDER IC_SORDER,
RID.UNIT ID_UNIT
FROM
RF_ITEMDETAILS RID,
RF_ITEMCONFIG IC,
RF_GROUPCONFIG GC,
RF_PRODUCTCONFIG PC
WHERE
-- Item Configuration
IC.ITEMID = RID.ITEMID
AND IC.VISIBLE = 'Y'
-- Group Configuration
AND GC.GROUPID = IC.GROUPID
AND GC.VISIBLE = 'Y'
-- Product Configuration
AND PC.PRODUCTID = GC.PRODUCTID
AND PC.VISIBLE = 'Y'
-- Order by
ORDER BY
PC.SORTING_ORDER,
CASE WHEN PC.SORTING_TYPE = 'N' THEN GC.SORTING_ORDER END,
CASE WHEN PC.SORTING_TYPE = 'A' THEN GC.DESCRIP END,
CASE WHEN GC.SORTING_TYPE = 'N' THEN IC.SORTING_ORDER END,
CASE WHEN GC.SORTING_TYPE = 'A' THEN IC.DESCR END