Page 55 - TCS ICT Book 8
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The City School 2021-2022
• To work with records from more than one table, you
often must create a query that joins the tables.
• The query works by matching the values in the
primary key field of the first table with a foreign key
field in the second table. Advance Imaging Handling Databases with Research
• When you design a form or report, MS Access uses
the information it gathers from the table relationships
you have already defined to present you with
informed choices and to prepopulate property
settings with appropriate default values.
Primary Key
A primary key, also called a primary keyword, is a
key in a database that is unique for each record. It is
a unique identifier, such as a driver license number,
telephone number (including area code), or vehicle
identification number (VIN). A relational database
must always have one and only one primary key.
Primary keys typically appear as columns in relational
database tables.
Foreign Key
A foreign key is a column or group of columns in a
relational database table that provides a link between
data in two tables. It acts as a cross-reference
between tables because it references the primary key
of another table, thereby establishing a link between
them.
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