Data warehouses (almost) always need an explicit date dimension table. The number of rows in the date dimension is usually fixed. The dates are not sourced from the operational database. Calculate the number of rows in the following Date Dimensions a) Suppose that we need the day as a grain in the Date dimension. How many rows in the Date dimension table if we store 10 years days are in the Date dimension table? b) Suppose that we need time in data warehouse in order to answer managers question. That is, the second should be used as a grain. How many rows in the Time dimension table? c) Should we store the second in a 10 years Date dimension table? Or we separate time of the day in a Time dimension? Data warehouses (almost) always need an explicit date dimension table. The number of rows in the date dimension is usually fixed. The dates are not sourced from the operational database. Calculate the number of rows in the following Date Dimensions a) Suppose that we need the day as a grain in the Date dimension. How many rows in the Date dimension table if we store 10 years days are in the Date dimension table? b) Suppose that we need time in data warehouse in order to answer managers question. That is, the second should be used as a grain. How many rows in the Time dimension table? c) Should we store the second in a 10 years Date dimension table? Or we separate time of the day in a Time dimension