Access
tables are classified as the 1k
Daily Profit Review primary building block of an Access database.
They're 2-dimensional constructions which consist of rows (records)
and columns (fields) and the theory inside of a relational database
setting is that information is split up into discrete data structures
and preserved in a number of related tables.
In
a database intended for a teaching institute rather than have one
huge table that contains all the info about every student and every
individual course which they might attend it is better to provide
just one table for students and one for courses which has a relation
relating to the two. There are two forms of relationships;
One-To-Many and Many-To-Many. A One-To-Many relationship indicates
that one record can exist many times in another table.
As
an example, a class is taught by just one teacher therefore we
express that "one particular teacher teaches many classes".
A class, on the other hand, can easily consist of many students but a
student may additionally be present at many classes. This is why we
say that the students and classes require a "Many-to-Many"
relationship. In this case a junction table is needed between the two
tables.
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