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Assumption: this data you are de-duping is downloaded fresh, daily from TwitFace.

The idea of loading 180 million records into a db on disk in order to de-dup it is ridiculous if you are in any way concerned with speed.

The following shows a 10-line perl script de-duping a 200-million line, 2.8 GB file of 12-digit numbers in a little over 2 1/2 minutes, using less than 30 MB of ram to do so:

C:\test>dir 1054929.dat 20/09/2013 04:22 2,800,000,000 1054929.dat C:\test>wc -l 1054929.dat 200000000 1054929.dat C:\test>head 1054929.dat 100112321443 100135127486 100110839892 100098464584 100098900542 100048844759 100090430059 100018238859 100132791659 100027638968 C:\test>1054929 1054929.dat | wc -l 1379647642.87527 1379647855.6311 113526721

That's processing the 12-digit numbers at a rate of just under 1 million per second.

You cannot even load the data into the DB at 1/100th of that rate; never mind get the de-duped back out.


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In reply to Re: DBI::SQLite slowness by BrowserUk
in thread DBI::SQLite slowness by Endless

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