What about archived records? You could archive by date on a daily, weekly, or monthly basis. I used this method in a large system developed for a repair factory that needed an sales and inventory system. I created history tables that matched the 'live' tables (table name was H... and stored in an 'archive' server -- just be sure to use a logical table naming schema or store them in a separate location) so the data could be accessed for historical reports and audits if necessary and added historical menu items to the main system.

Tracy

>hi,
>I am developing stock control system. Recently, my client complain that my report generated very slowly. According to my investigation, it is because amount of data. This client has 25,000 products. Also, it could has 500 sales records and average 30 lineitems per sale within ONE DAY.
>Therefore, I am worry about the performance of the query.
>I was told that we should purge our data periodly.
>Could you please give me some ideas?
>Where does the purged data should be stored?
>Could it able to be restored?
>Once purged, how could I refer to previous data when necessary? Do you generate summary record for each table or...?
>
>Pls advise
>
>Thank you