python - How do I exclude columns when exporting app engine data -

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i'm planning data mining on django app uses appengine storing data, however, 1 of tables stores images in 2 of it's columns, , because of that, gigabytes in size it's far slow download every time want analyse new data. data mining, care plan text columns in table, how exclude columns while exporting data csv file?

i'm aware there "column_list" csv connector buildupload.yaml can specify include columns when exporting data, looks still downloads entire table row before filtering out columns when it's converting appengine's intermediate sqlite3 data file csv.

for reference, i'm using method described here download data http://code.google.com/appengine/docs/python/tools/uploadingdata.html, i'm open other solutions, preferably ones can automate data export every few days.

as you've observed, bulkloader downloads entire record using remote_api, outputs fields care csv. if want download selected fields, you'll have write own code on server-side - possibly using new files api in mapreduce, write file can download.


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