sql - Table Design For Multiple Different Products On One Order -

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if have online shopping website sold apples , monitors , these stored in different tables because distinguishing property of apples colour , of monitors resolution how add these both invoice table whilst still retaining referential integrity , not unioning these tables?

                        invoices(invoiceid)                                  |                   invoiceitems(itemid, productid)                                  |                        products(productid)               |                                            | apples(appleid, productid, colour)   monitors(monitorid, productid, resolution)

in first place, store them in single products table, not in 2 different tables.

in second place, (unless each invoice 1 product) not add them single invoice table - instead, set invoice_products table, link between tables.

i suggest database normalisation.


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