Recycled firm
The firm has a few outlets that receive items for recycling. Each of the outlets receives funds to be paid to deliverers.
Information on received funds is registered in a table:
Income_o (point, date, inc)The primary key is {point, date}, thus receiption of money (inc) takes place not more than once a day (date column does not include time component of the date). Information on payments to deliverers is registered in the table:
Outcome_o (point, date, out)In this table the primary key {point, date} also ensures bookkeeping of the funds distribution at each point not more than once a day.
In case incomes and expenses may occur more than once a day, another database schema is used. Corresponding tables include code column as primary key:
Income (code, point, date, inc)
Outcome (code, point, date, out)In this schema date column does not also include the day time.