php - How does Google Reader download feeds in the background? -


a lot of rss feeds show limited number of items, meaning when load feed load latest 10 items example. when using google reader load many more if not in sites rss feed when load it. downloading of these feeds database when user not on site? how work?

if downloading feeds in background, best , efficient way this? can imaging storing in table big , data intensive if done incorrectly.

is downloading of these feeds database when user not on site?

yes

how work?

by not tying code fetches data , populates google's databases code outputs html et al ui.

it done simple cron job or dedicated daemon.

if downloading feeds in background, best , efficient way this? can imaging storing in table big , data intensive if done incorrectly.

there entire books on subject (which makes unsuitable stackoverflow question).

you underestimate efficiency of standard rmdbs though, unlikely dealing data @ anywhere near scale google , rmdbs fine purposes. if outgrow it, outgrow , can @ other options (of there quite lot, including sharding , nosql databases), don't optimise prematurely.


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