java - Write Excel data directly to OutputStream (limit memory consumption) -

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i’m looking – simple – solution output big excel files. input data comes database , i’d output excel file directly disk keep memory consumption low possible. had things apache poi or jxls found no way solve problem.

and additional information need generate .xls files pre 2007 excel, not new .xlsx xml format. know generate csv files i’d prefer generate plain excel…

any ideas ?

i realize question isn't clear, want able write excel file without having keep whole in memory...

the way efficiently use character-based csv or xml (xlsx) format, because can written output line line can per saldo have 1 line @ once in memory time. binary-based xls format must first populated completely in memory before can written output , of course memory hogging in case of large amount of records.

i recommend using csv may more efficient xml, plus have advantage decent database server has export capabilities that, don't need program/include new in java. don't know db you're using, if example mysql, have used load data infile this.


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