February 2014
Beginner
1248 pages
62h 25m
English
Content preview from Java™ How To Program (Early Objects), Tenth Edition
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Section 24.2 Relational Databases
• A relational database (p. 1047) stores data in tables (p. 1047). Tables are composed of rows (p. 1047), and rows are composed of columns in which values are stored.
• A table’s primary key (p. 1047) has a unique in each row.
• Each column (p. 1047) of a table represents a different attribute.
• The primary key can be composed of more than one column.
• An identity column is the SQL standard way to represent an autoincremented (p. 1048) column. The SQL IDENTITY keyword (p. 1048) marks a column as an identity column.
• A foreign key is a column in a table that must match the primary-key column in another table. This is known as the Rule of Referential Integrity (p. 1050).
• A one-to-many relationship (p. 1051 ...
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