6 Replies Latest reply on Nov 2, 2015 10:51 PM by mactune08

    Tables or TO's?

    mactune08

      What would be the best way to show a history of the relocation of products to different rooms in a building? The products are made up of different manufacturers and have different model and serial numbers and are serviced by different technicians and are sometimes moved to different locations.

       

      Would I need a different table for the history of these moves, services, technicians or only one table for the location of these products and then a TO for the history?

       

      Any guidance would be much appreciated, thanks!

        • 1. Re: Tables or TO's?
          jbrown

          Hi.

          I see the history as a separate entity, thus a separate table. It is like school years for students–I want to see each school year what grade / homeroom a student was in.

           

          In your case, I guess you have to ask yourself: do I need to see the history of a product? Do I need to see where it was 3 years ago? If so, then make a history table and simply put in the product ID and any data that could change between the years (Obviously Location. I don't think Serial number would change).

          • 2. Re: Tables or TO's?
            coherentkris

            I see PRODUCTS, LOCATIONS, MANUFACTURERS, MODELS, TECHNICIANS, SERVICE EVENTS and MOVES (or LOCATION CHANGE TRANSACTIONS) entities. Location history is within MOVES.

            Serial number, manufacturer, and model are attribute of a product.

            • 3. Re: Tables or TO's?
              beverly

              for clarity, they are ALL TO's (table occurrences as on the 'graph')

               

              I think you mean a JOIN table (TO) or other RELATED table (TO).

               

              Yes, for 'historical' information about anything a related (or join) table is preferred.

               

              If you have relationships between two tables, a third (JOIN) table is also preferred, if the two tables are main tables. You may only need the relationship to the historical data (a relationship).

              • 4. Re: Tables or TO's?
                mactune08

                Thanks Jeremy for prompt answer. It is important to see all relevant history of a product until it is out of service and sold. Then it can move out of the current inventory table and reside in a separate "historical" table for future referral.

                • 5. Re: Tables or TO's?
                  mactune08

                  Agree with all the entities you have mentioned. Not sure if i would need one or two TO's of MOVES?

                  • 6. Re: Tables or TO's?
                    mactune08

                    Hi Beverly, thank you for clarifying the TO's. I had meant to ask if I would need two TO's for the same MOVES table