What should my daily intake of calories be? Within a healthy, balanced diet, a man needs around 10,500kJ (2,500Kcal) a day to maintain his weight. For a woman, that figure is around 8,400kJ (2,000Kcal) a day. These values can vary depending on age, metabolism and levels of physical activity, among other things.
A foreign key, simply stated, is another table's primary key. The values in a foreign key field match values in the primary key, indicating that the two records are related â for example, a customer and an order that she has placed. Unlike primary keys: A table can have more than one foreign key.
Foreign Keys and Referential Integrity. A foreign key relationship allows you to declare that an index in one table is related to an index in another and allows you to place constraints on what may be done to the table containing the foreign key.The database enforces the rules of this relationship to maintain referential integrity.oreign Keys and Referential Integrity. A foreign key relationship allows you to declare that an index in one table is related to an index in another and allows you to place constraints on what may be done to the table containing the foreign key.