CS157a
Chris Pollett
Oct 2, 2019
name | street | city | title | year C. Fisher | 123 Maple St. | Hollywood | Star Wars | 1977 C. Fisher | 5 Locust Ln. | Malibu | Star Wars | 1977 C. Fisher | 123 Maple St. | Hollywood | Empire Strikes Back | 1980 C. Fisher | 5 Locust Ln. | Malibu | Empire Strikes Back | 1980 C. Fisher | 123 Maple St. | Hollywood | Return of the Jedi | 1983 C. Fisher | 5 Locust Ln. | Malibu | Return of the Jedi | 1983
name | street | city | title | year C. Fisher | 123 Maple St. | Hollywood | Star Wars | 1977 C. Fisher | 5 Locust Ln. | Malibu | Empire Strikes Back | 1980
We can modify our BCNF decomposition algorithm to get a 4NF decomposition algorithm as follows:
In the case of our earlier example table. The above algorithm would split the table because of `n\a\m\e ↠ s\t\r\e\e\t \ \ c\i\t\y` and decompose it into two tables `R_1`(name, street, city) and `R_2`(name, title, year).