> ### How data compacting works

> When you run FathomTrendDatabase compaction (as a job), the compaction takes a number of the records and compacts them in a different table in the FathomTrendDatabase. For example, the compaction might take the first four records in the table and combine them into one record in the archive table.

> Note that as part of the compaction process, the records physically move to the archive table, so they are deleted from the real-data table. The archive automatically creates an hourly, daily, and weekly version of each sample, as follows:

> - Hourly — Takes all the data for an hour and compacts it into one record for that hour. This compaction method takes records for one hour and reduces them to one row.
> - Daily — Takes all the data for a day and compacts it into one record for that day. This compaction method takes records for one day and reduces them to one row.
> - Weekly — Takes all the data for seven days and compacts it into one record. The day technically begins at midnight on Saturday night. This method takes records for seven days and reduces them to one row.
> Caution: There is no option to undo the deletion of data samples from a real-data table following the compaction.

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