Tables that have an unexpectedly large number of rows in them may indicate a problem. You can either DELETE or TRUNCATE the table. DELETE option is a more measured approach, whereas the TRUNCATE option empties the table. For DELETE you can do so in small chunks, by date; however, this process will be slower.
For example, if one of your large tables is dbo.PassiveMonitorActivityLog then you can select a date, where all entries prior to that date will be deleted. Let us say you want to delete all entries in the dbo.PassiveMonitorActivityLog table prior to 1/1/2012 then run the following command:
DELETE FROM dbo.PassiveMonitorActivityLog WHERE dEventTime < ‘1/1/2012′
If the Statistical tables are the ones that happen to be large, then choose to either DELETE or TRUNCATE.
DELETE FROM dbo.StatisticalPing WHERE dPollTime < ‘1/1/2012′
Alternatively, you can empty a table’s contents by running this query:
TRUNCATE Table dbo.StatisticalPing
Then repeat what you did using Database Utilities