Relational programming is nonprocedural and operates on a set of rows at a time. In
a master-detail relationship between tables, there can be one or many detail rows for
each individual master row, yet the statements used to access, insert, or modify the
data simply describe the set of results. In many early relational databases, data access
required the use of procedural languages that worked one record at a time. Because
of this set orientation, programs access more than one record in a relational database
more easily. Relational databases can be used more productively to extract
value from large groups of data.
The contents of the rows in Figure 1-2 are sometimes referred to as records. A column
within a row is referred to as a field. Tables are stored in a database schema,
which is a logical organizational unit within the database. Other logical structures in
the schema often include the following:
Views
Provide a single view of data derived from one or more tables or views. The view
is an alternative interface to the data, which is stored in the underlying table(s)
that make up the view.
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