[Database Explodes With Lots Of Statistics]

I'm pretty sure that it will keep all stats, forever.

 

I also have all stats from the beginning:

mysql> select count(1) from ox_data_intermediate_ad;
+----------+
| count(1) |
+----------+
| 16393410 |
+----------+
1 row in set (0.00 sec)

First record:

mysql> select * from ox_data_intermediate_ad limit 1\G
*************************** 1. row ***************************
data_intermediate_ad_id: 2
              date_time: 2010-02-10 17:00:00
     operation_interval: 60
  operation_interval_id: 89
         interval_start: 2010-02-10 17:00:00
           interval_end: 2010-02-10 17:59:59
                  ad_id: 4
            creative_id: 0
                zone_id: 1
               requests: 0
            impressions: 156
                 clicks: 5
            conversions: 0
     total_basket_value: 0.0000
        total_num_items: 0
                updated: 2010-02-10 18:05:02
1 row in set (0.00 sec)

Last record:

mysql> select * from ox_data_intermediate_ad order by date_time desc limit 1\G
*************************** 1. row ***************************
data_intermediate_ad_id: 44052257
              date_time: 2014-04-22 14:00:00
     operation_interval: 60
  operation_interval_id: 62
         interval_start: 2014-04-22 14:00:00
           interval_end: 2014-04-22 14:59:59
                  ad_id: 16830
            creative_id: 0
                zone_id: 13
               requests: 0
            impressions: 31
                 clicks: 0
            conversions: 0
     total_basket_value: 0.0000
        total_num_items: 0
                updated: 2014-04-22 15:00:02
1 row in set (0.00 sec)