APEX

Hi all,

I would like to update my table QTMT_TICKETS by a form created from the table QTMT_TICKETS, but I change one of the Page Item's Source Type from: Database Column to Source Type: SQL Query (return single value). This item contain an SQL expression. When I run the page I can see the value from the SQL query in the form, but when I press Update button, then this value is not updated in the table.
Is there any way to update the table by the SQL expression value?

I also tried to create an additional PL/SQL process on the form page:
begin
update QTMT_TICKETS
set GATE_COMM_ID = :P20_GATE_COMM_ID
where TICKET_ID = :P20_TICKET_ID;
end;

But it insert only an empty value "-" in the cell of the table.

Could you please let me know what I do wrong in the additional process or if there is a way of updating the table just by the form update process?

Thank you and best regards,

Vladimir