Number of currently displayed rows in report with pagination?

Question

Maybe I'm thinking to complicated, but ...
In my report I use the HTMLDB_ITEM.CHECKBOX function in order to display a checkbox for each row:
HTMLDB_ITEM.CHECKBOX(1,"ID",NULL,:P311_ASSIGNED,':') " "
Some of the checkboxes are selected depending on whether there is an entry for them in a database table.
As the report returns hundreds of rows, I use pagination (e.g. 15 rows per page).
After checking/unchecking the checkboxes and submitting the page by clicking the save button, I want to do the following: For each row CURRENTLY DISPLAYED on the screen (1) check, whether its checkbox is currently checked or not (2a) If it is checked and there is not yet an entry -> add row to the db table (2b) If it is unchecked and there is an entry in the db table -> remove row from db table.
How can I, on the server side, find out which rows (row ids) are currently displayed (using pagination), so that I check each of the currently displayed row ids for their existence in the database table? Is there any item stored on the server side, which tells me the row number of the first row currently displayed? Is there an item I can refer to, which tells me the amount of rows, which are displayed on one page?
Your help would be very much appreciated!
Konrad

Answer 1

Hi Konrad,
I will jump in. :-) Just have a few minutes before a meeting.
I think you don't have to make it that complicated, where you have to know the current pagination.
1) Your HTMLDB_ITEM.CHECKBOX has to contain as checked value #ROWNUM# as the row selector would do it.
2) You have to create a hidden item where you store your customer id
3) create another hidden item where you store if the customer has already the assignment
4) In your process you are now able to loop through your arrays.
DECLARE
    vRowNumber BINARY_INTEGER;
    vFound BOOLEAN;
BEGIN
    -- insert new event assignments
    FOR ii IN 1 .. WWV_Flow.g_f01.COUNT -- your checkbox
    LOOP
        vRowNumber := WWV_Flow.g_f01(ii);
        -- no assignment yet?
        IF WWV_Flow.g_f03(vRowNumber) IS NULL -- your hidden field where you store if you have an assmnt
        THEN
            INSERT INTO xxx VALUES (WWV_Flow.g_f02(vRowNumber)); -- your customer id
        END IF;
    END LOOP;
    -- delete old event assignments
    FOR ii IN 1 .. WWV_Flow.g_f03.COUNT -- your hidden field where you store if you have an assmnt
    LOOP
        -- only if the event was already assigned
        IF WWV_Flow.g_f03(ii) IS NOT NULL
        THEN
            vFound := FALSE;
            FOR jj IN 1 .. WWV_Flow.g_f01.COUNT -- your checkbox
            LOOP
                -- is the event still checked?
                IF WWV_Flow.g_f01(jj) = ii
                THEN
                    vFound := TRUE;
                    EXIT;
                END IF;
            END LOOP;
            IF NOT vFound
            THEN
                DELETE xxx WHERE CUSTOMER_ID = WWV_Flow.g_f02(ii);
            END IF;
        END IF;
    END LOOP;
END LOOP;Haven't tested the code, but I think it should show the idea.
Hope that helps
Patrick
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