Can anyone point me to a practical application of cursor()
to do pagination?
I am not clear how to use cursor()
as given in the documentation.
This is my query:
items = db.GqlQuery("SELECT * FROM Item ORDER BY date DESC LIMIT 30")
which I render like this:
self.response.out.write("<ol>")
for item in items:
self.response.out.write("""<li><a href="/vote/%s?type=%s"> ^ </a><a href="%s">%s</a> <span id='Small'>(%s)</span><br />
<div id='Small'>
%s points %s by %s <a href="/item/%s"></a> |
<a href="/item/%s#disqus_thread"></a></div>
</li><br /> """ %
(str(item.key().id()), merchandise_type, item.url, item.title, urlparse(item.url).netloc,
item.points, item.date.strftime("%B %d, %Y %I:%M%p"), item.user_who_liked_this_item, str(item.key().id()), str(item.key().id())))
self.response.out.write("</ol>")
Thanks!
UPDATE
Hi Amir: Thanks for your answer but I could't make this link work. Here's what I have:
#===========adding cursor here===========#
cursor = self.request.get("cursor")
if cursor: query.with_cursor(cursor)
items = query.fetch(30)
cursor = query.cursor()
#===========adding cursor here===========#
#===========regular output===========#
self.response.out.write("<ol>")
for item in items:
self.response.out.write("""<li>
<a href="/vote/%s?type=%s"> ^ </a><a href="%s">
<span id="large">%s</span></a>
<span id='Small'>(%s)</span>
<br />
%s<br /> <span id='Small'>
%s points %s by %s <a href="/item/%s"></a> |
<a href="/item/%s#disqus_thread"></a>
</span>
</li><br /> """ %
(str(item.key().id()), merchandise_type, item.url,
item.title, urlparse(item.url).netloc,
item.summary, item.points, item.date.strftime("%B %d, %Y %I:%M%p"),
item.user_who_liked_this_item, str(item.key().id()),
str(item.key().id())))
self.response.out.write("</ol>")
#===========regular output===========#
#===========link to cursor===========#
self.response.out.write("""<a href="/dir?type=%s?cursor=%s">Next
Page</a>""" % (merchandise_type, cursor))
But this results in this url which displays nothing:
http://localhost:8083/dir?type=newest?cursor=E9oBdgoTc2FyYWgtZm9yLXByZXNpZGVudBoESXRlbUtSBGRhdGVYAkwhQ1VSU09SIWoiahNzYXJhaC1mb3ItcHJlc2lkZW50cgsLEgRJdGVtGKsCDHIVCAcaBGRhdGUgACoJCMid8OXW4qYCggELCxIESXRlbRirAgzgAQAU
Update 2
See @Amir comment below: changing the second ?
to &
solved the problem. Thanks!
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