Accuracy of time stamping of data and trigger

Hello, bubblers.
I am now planning to build a big system of auction, like EBAY.

The number of users is estimated to 2000 when the auction’s deadline is coming.
I want to know the accuracy of time stamping of data record.
Does anybody know How many decimal places can be measured and recorded into the database as “Created date”?

Timestamps are in milliseconds (thousandths of a second).


OK, thank you.