database driven mega menu sql

Hello, I want to create a mega menu from sql databse items.
the menu is like this:
item1 item2 item3 item4
and forexample for submenus of item 1:
item1-1        item 1-2        item 1-3
item 1-1-1     item 1-2-1      item 1-3-1
item 1-1-2     item 1-2-2       item 1-3-2
can any body help me about this, I don't have any idae about that, I googled the subject, but couldn't find any thing.
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