Database Reference
In-Depth Information
new_skip
=
skip
-
page
[
'count'
]
iif
new_skip
>=
0
:
skip
=
new_skip
continue
continue
elif
elif
skip
>
0
:
comments
=
page
[
'comments'
][
skip
:]
else
else
:
comments
=
page
[
'comments'
]
skip
=
new_skip
for
for
comment
iin
comments
:
iif
limit
==
0
:
break
break
limit
-=
1
yield
yield
comment
iif
limit
==
0
:
break
break
Here, we iterate through the pages until our
skip
requirement is satisfied, then
yield
com-
ments until our
limit
requirement is satisfied. For example, if we have three pages of com-
ments with 100, 102, 101, and 22 comments on each page, and we wish to retrieve comments
where
skip=300
and
limit=50
, we'd use the following algorithm:
Skip Limit Discussion
300 50
Page 0 has 100 comments, so
skip -= 100
.
200 50
Page 1 has 102 comments, so
skip -= 102
.
98 50
Page 2 has 101 comments, so set
skip=0
and return last 3 comments.
0
47
Page 3 has 22 comments, so return them all and set
limit-= 22
.
0
25
There are no more pages; terminate loop.
Operation: Retrieve a comment via direct links
To retrieve a comment directly without paging through all preceding pages of commentary,
we'll use the slug to find the correct page, and then use application logic to find the correct
comment:
page
=
db
.
comment_pages
.
find_one
(
{
'node_id'
:
node_id
,
'comments.slug'
:
comment_slug
},
