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Also called a Key field.

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15y ago

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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.


How is a relationship created in SQL Server?

In the table design view, right click the column name of the entity you want to create a relationship with and then select "Relationships" which opens the Properties window with the Relationships tab selected. Click on "New" and then verify the "Primary key table" and "Foreign key table". Select the primary key from the grid below the "Primary key table" name (left side of grid) and then select the column name you right-clicked on earlier from the grid below the " Foreign key table" name (right side of grid). Selecting each one in turn sets the two into the desired relationship.


All types of keys in database?

* Alternate key - An alternate key is any candidate key which is not selected to be the primary key * Candidate key - A candidate key is a field or combination of fields that can act as a primary key field for that table to uniquely identify each record in that table. * Compound key - compound key (also called a composite key or concatenated key) is a key that consists of 2 or more attributes. * Primary key - a primary key is a value that can be used to identify a unique row in a table. Attributes are associated with it. Examples of primary keys are Social Security numbers (associated to a specific person) or ISBNs (associated to a specific book). In the relational model of data, a primary key is a candidate key chosen as the main method of uniquely identifying a tuple in a relation. * Superkey - A superkey is defined in the relational model as a set of attributes of a relation variable (relvar) for which it holds that in all relations assigned to that variable there are no two distinct tuples (rows) that have the same values for the attributes in this set. Equivalently a superkey can also be defined as a set of attributes of a relvar upon which all attributes of the relvar are functionally dependent. * Foreign key - a foreign key (FK) is a field or group of fields in a database record that points to a key field or group of fields forming a key of another database record in some (usually different) table. Usually a foreign key in one table refers to the primary key (PK) of another table. This way references can be made to link information together and it is an essential part of database normalization


what field is used as a primary key?

We explicitly choose a primary key.A primary key should satisfy the following conditions: 1) it should not be null 2) it should be unique.


Can you insert primary key only to one field in the database?

Yes. Primary key can be inserted to one field in the database. The field should be unique and not null.

Related Questions

Another name for the primary key is the key?

Index key


What is a primary key of one file that appears in another file?

A primary key is one that uniquely identifies a record . Also there are cases when primary key of one file appears in another file. In that case the key is called Foreign key.


Another term for major key?

Primary Sort Key


What does the term foreign key mean in databases?

The foreign key is used as a reference in a table to the primary key of another table. For example: consider a table employee with id(primary key), name, address,department_id(foreign key) as its fields.Another table department with fields department_id(primary key) and dept_name. So, department_id is primary key in department table and foreign key in employee table.


When foreign key is used?

A foreign key is when a value of one table, which is a primary key of another table. Manufacturer_table - id - name Models_table - id - manufacturer_id - name Models_table.manufacturer_id should be defined is a foreign key to the Manufacturer_table.id column


Is the last name a primary key?

A primary key is always unique and not null. It is prefer to choose a field that is unique like roll number . But to choose Last name as a primary key is not a good option as two people can have same last name.A Last name field is not a good one for a primary key. A primary key cannot have duplicate values. A last name field is highly likely to have duplicate values, so it should not be used as a primary key.


What is another term for major key in access 2007?

Primary Sort key


Can the FirstName column be a primary key?

A First name field is not a good one for a primary key. A primary key cannot have duplicate values. A first name field is highly likely to have duplicate values, so it should not be used as a primary key.


What is another term for unique identifier?

primary key


What ensures the value of the foreign key matches another tables primary key?

It is the DBMS that ensures the value of the foreign key matches another table's primary key when referential integrity constraints are enabled within the DBMS


What is difference between primary key and foreign key?

A primary key is an attribute (or combination of attributes) that uniquely identifies each row in a relation. A primary key is designated by underlining the attribute name. The primary key of an entity set allows us to distinguish among the various entities of the set. A foreign key is an attribute in a relation of database that serves as the primary key of another relation in the same database.


What is another name for primary storage devices?

the another name for primary storage is main storage device.