how to delete all activities from database

[kennedy]

what is the best way to delete all activities from a MySQL database without risk damage to data integrity?
MySQL command will be of great help. Using MySQL version  5.5.35

Thank you in advance!

[andrewhunt]

The safest (and easiest) way to delete anything in bulk in CiviCRM is through the bulk actions you get from searching.  Use the Find Activities option in the menu, and simply hit Search without setting any criteria.  That'll return all activities, and from there, you can choose all records and use the Delete Activities option in the Actions dropdown that's at the top of the results.

Now, if you have contributions, event registrations, etc., those also appear as activities, and I'm not sure what the behavior is if you try to delete those activities.  I suspect one of the following
- it prevents you from deleting them
- you delete the activity, but the contribution still exists
- you end up deleting both.

You might try creating something on the demo site and experimenting with that.  If you decide those activities are worth keeping, you should use the search criteria in the Find Activities search to just select the activity types you want to clear out.

[kennedy]

thanks Andrew, this will work and it doesn't delete the events registration, I have no contributions either.

[Dennis Gray]

CiviCRM 4.1.5

I have been asked to delete all activities over one year old. When I use the UI (Find Activities), I get nothing but a white screen. I suppose it's timing out. Since our database goes back to 2008 or earlier, it would be a tedious process to go through each month of data.

Is there a way to do this using a SQL statement? What tables would be involved?

[kennedy]

have you tried deleting them in batches?

[Dennis Gray]

Yes. Our database goes back to 2008, as I mentioned. To delete in batches would be very time consuming as I only seem to be able to delete a month at a time.  I'm looking for a way to delete from the database without going through the UI.