Counter History repeating dates on each visit

Hi,
I've searched through the forums with little or no solution to my prob - so sending out an SOS!

I've just recently upgraded from 1.3.8 to 1.3.9h, very time consuming, but slowly, and finally, it all looks ok. APART FROM - the counter history table in my admin repeats on each page visit by a customer.

Whereas it should read:
14/12/11 500 - 800
13/12/11 400 - 600
12/12/11 700 - 900 etc

It reads:
14/12/11 2 - 4
14/12/11 2 - 4
etc etc ad nauseum

The counter works, and increases one per visit, but adds another line for 14/12/11 (or relevant date) rather than just keeping it one line per day.

I've checked the counter_history table in the db and it also reflects this, and has only been doing this since yesterday (when i added google analytics mod incidentally, and moved everything from 'demo' to 'live' as suggested in the upgrade process.)

Would I have missed something when updating the configure files? I've checked and double checked but i'm stuck! Is it a simple cache clearing required?

I know this is really a minor irritation but i'd like to clear it up!

Any help appreciated,
Kev

I've tracked down the solution!

I went into phpMyadmin and selected counter_history table.

I scanned through the entries, deleting each duplicate line.

I then selected 'structure' under the counter_history table.

I then clicked the yellow key titled 'primary key' to the right of the 'startdate' line.

Presto! No more duplicates!