I have a table in my database containing a linked list.
ID | page | prior | next
1 | A | 0 | 2
2 | B | 1 | 3
3 | C | 2 | 4
4 | D | 3 | 5
5 | E | 4 | 0
How do I display all the items in this table? A SORT BY wouldn't work after a few positional swaps and insertions. I'm using Flask, which uses Jinja2 templates. My current approach is to locate the first item and add it to a list. Then, based on the previous item's "next" value, collect the next row and add it to the list.
num_rows = Pages.query.count()
# find first row, the one where prior is 0
first_row = Pages.query.filter_by(prior=0).first()
# create a list containing just the first row for now
all_rows = [first_row, ]
# add new rows to the list
for i in range(0, (num_rows-1)):
current_row = all_rows[i].next
all_rows.append(Pages.query.get(current_row))
Finally, I pass the list to render_template('template.html', all_rows = all_rows), then retrieve it in the template.
Surely there's a more elegant approach? I imagine that this would perform terribly and require lots of resources?
