faramarz_s
شنبه 16 اسفند 1382, 17:22 عصر
Enforced and Unenforced Relationships in Database Diagrams
Creating a relationship line in a database diagram automatically enforces referential integrity by creating a foreign key constraint on the related table. An enforced relationship appears in your database diagram as a solid line. For example:
An unenforced relationship, whose foreign key constraint is disabled, appears in your diagram as a dashed line. For example:
Depending on the features of your database, you can set options to disable the foreign key constraint for certain conditions, for example, during INSERT and UPDATE transactions.
1-در مورد پاراگراف اول و دوم توضیح بفرمایید؟
2-در پاراگراف آخر چگونه این constraintرا می توان غیر فعال نمود؟
Creating a relationship line in a database diagram automatically enforces referential integrity by creating a foreign key constraint on the related table. An enforced relationship appears in your database diagram as a solid line. For example:
An unenforced relationship, whose foreign key constraint is disabled, appears in your diagram as a dashed line. For example:
Depending on the features of your database, you can set options to disable the foreign key constraint for certain conditions, for example, during INSERT and UPDATE transactions.
1-در مورد پاراگراف اول و دوم توضیح بفرمایید؟
2-در پاراگراف آخر چگونه این constraintرا می توان غیر فعال نمود؟