I am building a price comparison site that holds about 300.000 products and several hundred clients.
On a daily basis the site needs updating of prices and vendor stock availability.
When a vendor needs updating I was thinking about deleting all the vendor information and then pulling and inserting a new - each time.
Doing this I don't have to worry about a vendor deleting a product. In a simple way I would get a new set of data each day.
On the other hand I need to keep the autoincrement counter in check and it seems a waste to delete everything from a vendor if he has only updated prices on 3 products in his entire warehouse.
But updating has its disadvantages too. I still have to read out all data and compare each and every product price/availability to the data from the vendor, one product at a time. Also it's more complicated to notice products that gets deleted by the vendor.
How do I achieve updating in the most efficient and easy way?