Efficiency during generating huge reports

Hi all,

my questions is: how long approximately will it take for a big company to generate 1 million of 1-page pdf reports? They are going to be filled with 20 various data field from Oracle database and generated with using REST Webservice API. Obviously, I know it depends on a lot of factors (i.e. hardware, configuration) but I need to estimate that time. Sorry if my question is silly, that's because of my lack of experience.

Thank you in advance :-)

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