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A foreign key field is a reference to data in another table. For example, assume that that government has a big list of names and social security numbers (or social insurance numbers, if you live in Canada). They have your SSN/SIN in one field and your name in another field and your address in a third field. Your SSN/SIN is a unique key that can be used to track data associated with you. Suppose now that the government wanted to put data about you in another table. Rather than copy all of your information, they decide that they are just going to put your SSN/SIN number in that other table instead. This is a good move, as they don't have to repeat data. But what if they enter the SSN/SIN incorrectly? That would cause trouble in the database. In order to solve this problem, foreign key fields are used. In the second table, the SSN/SIN field would be a foreign key field, meaning that whenever data is entered into that field, the database management system will automatically look up the data in the main database table to make sure that the SSN/SIN number exists. This allows the database management system to make sure that incorrect data is not added to a database table by mistake.
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What is the linking field in the many table called?
Foreign key field
Why is a field with an autonumber data type not a good candidate for the foreign key field for a one to many relationship?
The foreign key has to match the information from the corresponding record in the other table.
What is a field whose values are required to match the primary key in another table?
A Foreign Key.
When a record is identified by a combination of two field it is called what?
foreign key
Is a foreign key field always on the one side of a one-to-many relationship between two tables?
No. The foreign key is always on the many side. A foreign key is a field that is a primary key in another table, not in the table it is in. It can therefore be repeated in the table it is, so it can act as the many side. In its own table, it is the primary key, and only appears once.
True or false A foreign key is a field in one table that refers to the primary key field in another table and indicates how the the tables are related?
True.
What is a foreign key in Microsoft Access?
It is a field in one table that is a primary key in another table. It is used to create a relationship between two tables, normally a one to many relationship. The one side is where it is the primary key and where it is the foreign key, that is the many tables.
Difference between foreign key and composite key?
primary key: primary creates a clustered index on the column and it doesn't allow null values. unique key: unique key creates non clustered index by default.it allows "one null value". foreign key: A foreign key (FK) is a column or combination of columns used to establish and enforce a link between the data in two tables. Fore More information, you can visit this website:http://www.iyogibusiness.com
Is non key is same as those key that are not primary key?
A non-key field can be any field in the table that is not the primary key. During the process of normalisation identifying non-key fields is important, as they and other fields may be moved and new tables created. Foreign keys will be left in the table.
When a relationship exists between two tables in a database for Microsoft acess what name is given to the matching field in the related table?
The field in a related table that matches a field in another table is called a foreign key. This foreign key establishes the relationship between the two tables in a database.
When the primary key of one table is represented in a second table to form a relationship?
This is known as a "foreign key" (the data it points to is foreign to the current record). It is also commonly called a "foreign key constraint", usually in database systems where the database will perform additional data integrity checks when a primary key is updated or removed (such as restricting deletion of the primary record, clearing the value in the foreign key field, or cascading the deletion to the related records).
The key foreign policymakers are?
The key foreign policy makers are?
