java - Retrieving next N records in mongo db -

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i need scheduler job execute every 5 mins , process next 100 records mongodb collection. should start document inserted first. so, in first run, can sort data in ascending order , first 100 documents. consecutive runs, how can retrieve next 100 records giving last processed document's object id? (i'm not sure how use object id here generating string different parameters... don't have other id defined.)

if not way retrieve records mongodb large data set, please suggest better way.

each document looks below:

{ "_id" : { "$oid" : "51ff17c8e4b02969f18e72bb"} , "source_of_info" : "somesource" ,  "entityinfo" : [ { "user" : "alfredo vela zancada" , "social_network_entity_id" :   364221775325822977 , "text" : "blah blah blah" , "created_at" : { "$date" : "2013-08-  05t03:10:12.000z"}}] , "relatedurls" : [ { "url" : "http://t.co/swqp3fyqt5"   ,"expanded_url" : "http://ow.ly/nckis"}]}

thanks.

if keep track of iteration you're on use like:

db.users.find().limit(100).skip(1200)

another solution might add 'processed' flag each entry. default false. findandmodify when next 100 processed false, , modify them true.


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