I'm new at RSS. I need help to understand how RSS (and RSS reader) works.
Basically I have a JAVA program that runs every 5 minutes and creates an RSS XML file by grabbing data from database and put it into the file.
The RSS XML file looks like what I have in the code snippet:
My first question is:
How does an RSS reader work? How does it detect new item from an RSS feed? Does it detect new item based on uniqueID, guid element, or something else?
How often does an RSS reader will look for update?
(3.) When generating the RSS feed, it is possible for my RSS feed to have this case below:
Let say at minute 0, there's one item.
item with ID 0 and description element "lalalala"
then at minute 1, there's one more item.
item with ID 1 and description element "lililili"
so now there are two items listed in the file.
then at minute 2, the description element for ID 0 changed to "lolololo"
will RSS reader detect this?
<?xml version="1.0" encoding="ISO-8859-1"?>
<link>.....[this channel ink].....</link>
<description>.....[description about this channel].....</description>
<link>.....[link to this data].....</link>
<description>.....[description about this data].....</description>
<pubDate>Thu, 15 Nov 2007 09:13:42 PST</pubDate>