Deleting old logs/data

Hi there,

We need to get rid of old data.

If we follow this How do I delete historical Piwik data? (purge old logs and/or old processed reports) - Analytics Platform - Matomo , I’m assuming the report data will still be available from the Piwik UI, but cannot be ‘reprocessed’ again at any point?

So if I look up a date range for a site, will the report still be generated if the old files have been removed?


Date ranges would still work, even if you delete old “log data”, because they use the pre-processed “days”.

However don’t delete the “old report data” or you will lose data.

Thanks, Matt. Just wanted to be sure.

Matt, after setting Piwik to delete only LOG files older than 6 months, Piwik can no longer find ‘Month’ or ‘year’ or ‘date range’ data for any of my sites for 2013!!

I can see the data in the ‘piwik_archive_numeric_2013_’ and 'piwik_archive_blog_2013_’ tables in the database!!!

I thought (according to your previous reply here) that at the very least the ‘date range’ would work as ‘days’ & ‘weeks’ work?!

What has happened?


Oh wait, only ‘weeks’ are showing data for 2013!!!

Can someone please get back to me re this issue?

I can pull weekly reports for 2013, but if I try to pull ‘year’, ‘month’’, ‘day’ or ‘date range’ it says there is no data.

When I ran the log deletion it was purely the LOGS i chose to delete & we have had an hourly cronjob running since the system was installed.

Looking back at old cronjob logs from last year I get this what strikes me is that ‘day’ has NO visits shown…I’ve looked through most of them & with the old version of Piwik archiving looks like ‘day’ was not being archived???:

"- Reports for today will be processed at most every 3600 seconds. You can change this value in Piwik UI > Settings > General Settings.

  • Reports for the current week/month/year will be refreshed at most every 3600 seconds.
  • Archiving was last executed without error 45 min 0s ago
    Will process 4 websites with new visits since 45 min 0s , IDs: 1, 6, 9, 18

Starting Piwik reports archiving…
Archived website id = 1, period = day, Time elapsed: 0.131s
Archived website id = 1, period = week, 7013 visits, Time elapsed: 0.143s
Archived website id = 1, period = month, 29752 visits, Time elapsed: 0.143s
Archived website id = 1, period = year, 0 visits, Time elapsed: 83.693s’