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
08
Now that you’ve gone to the work of defining your relationship, it’s time to see what benefits you’ve earned. As in the real world, relationships impose certain restrictions. In the database world, these rules are called referential integrity. Taken together, they ensure that related data’s always consistent.
Note: Referential integrity comes into action only if you switched on the Enforce Referential Integrity option (Section 5.2.1) for your relationship. Without this detail, you’re free to run rampant and enter inconsistent information.
In the bobblehead example, referential integrity requires that every manufacturer you refer to in the Dolls table must exist in the Manufacturer table. In other words, there can never be a bobblehead record that points to a nonexistent manufacturer. That sort of error could throw the hardiest database software out of whack.
To enforce this rule, Access disallows the following three actions:
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Adding a bobblehead that points to a nonexistent manufacturer.
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Deleting a manufacturer that’s linked to one or more bobblehead records. (Once this record’s removed, you’re left with a bobblehead that points to a nonexistent manufacturer.)
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Updating a manufacturer by changing its ID number, so that it no longer matches the manufacturer ID in the linked bobblehead records. (This updating isn’t a problem if you use an AutoNumber field, because you can’t change AutoNumber values once you’ve created the record.)
Note: If you need to add a new doll made by a new manufacturer, you must add the manufacturer record first, and then add the doll record. There’s no problem if you add manufacturer records that don’t have corresponding doll recordsafter all, it’s perfectly reasonable to list a manufacturer even if you don’t have any of the dolls they’ve made.
Along with these restrictions, Access also won’t let you remove a table if it’s in a relationship. You need to delete the relationship first (using the Relationships window) and then remove the table.
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