Warning: strtotime() [function.strtotime]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 35
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 107
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 109
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 111
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 112
Feb
Warning: strtotime() [function.strtotime]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 35
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 107
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 109
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 111
Warning: date() [function.date]: It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'America/New_York' for 'EST/-5.0/no DST' instead in /home/frodr/public_html/msofficetuneup.com/wp-includes/functions.php on line 112
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It doesn’t matter how fancy your sales database isif it doesn’t have a way for customers to order the items they’re interested in, then Boutique Fudge will run out of money fast.
Database newbies often make the mistake of assuming that they can use one table to store order information. In truth, you need two:
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Orders records each order a customer places. It links to the customer who made the order, and adds information like the date the order was placed.
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OrderDetails lists the individual items in an order. Each record in the OrderDetails table includes the ID of the product that was ordered, the number of units ordered, and the price at which they were ordered.
Because the average order includes more than one item, a single record in the Orders table is usually linked to multiple records in the OrderDetails table (as shown in Figure 5-21). This setup may sound a bit awkward (because it means you’ll need to create a batch of new records for just one order), but the process doesn’t have to be that difficult. Access has two features that help out: the subdatasheet feature you’ve already seen (Figure 5-22) and the forms feature (Chapter 9).
Figure 5-21. Every order can hold an unlimited number of order items. This ability makes Boutique Fudge happy.
Figure 5-22. Thanks to the subdatasheet feature (Section 5.2.4), you can add an order record and the linked order items in the same place.
Notice that the OrderDetails record stores the price of each ordered item. This system may seem to violate the redundant data rule. After all, the product prices are always available in the Products table. However, product prices change, and companies offer discounts. For those reasons, it’s absolutely essential that you keep track of the price of an item when it was ordered. Otherwise, you’ll have to guess how much each customer owes you.
Note: Database nerds call this sort of information point-in-time data, because it varies over time.
You should also notice that the Order record doesn’t store the total cost of the order. That’s because the total cost is simply the sum of all the ordered items. If you stored a total cost, you’d open up the possibility of inconsistent datain other words, you’ve got a problem if the order total you store doesn’t match the cost of all the items.
You still have more work to do before Boutique Fudge can become a true databasedriven company. For example, you’ll probably need to create a Shipments table that tracks orders that it’s mailed and a Payments table that makes sure customers pay up. Conceptually, there’s nothing new here, but the more tables you add, the more complex your databases become. Now that you know the basics of relationships and good table design, you can stay cool under the pressure.
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