Author Question: Explain the steps in the process of putting a relation straight into Boyce-Codd Normal Form (BCNF). ... (Read 79 times)

EAugust · **on:** Jul 7, 2018

Explain the steps in the process of putting a relation straight into Boyce-Codd Normal Form (BCNF).

What will be an ideal response?

Question 2

What is an SQL script, and why are SQL scripts useful?

What will be an ideal response?

Jordin Calloway · **Reply #1 on:** Jul 7, 2018

Answer to Question 1

The steps are:
(1 ) Identify all functional dependencies in the relation.
(2 ) Identify every candidate key in the relation.
(3 ) Check to see if all determinants are candidate keys.
a. If so, the relation is in BCNF-STOP.
b. If not, then:
i. Move the columns of the functional dependency of the determinant that is not a candidate key to a new relation.
ii. Make the determinant of that functional dependency the primary key of the new relation.
iii. Leave a copy of the determinant in the original relation as a foreign key.
iv. Create a referential integrity constraint between the relations.
NOTE: If there is more than one functional dependency that needs to be moved, move the functional dependency with the most columns first.
(4 ) Repeat step (3 ) until you reach STOP.

Answer to Question 2

An SQL Script is a group of SQL statements that are run consecutively. Each of the SQL statements in the script could be run separately, but running them as a group is more efficient, and this is what makes SQL scripts useful. A good example is grouping all the SQL CREATE TABLE statements necessary to build a database structure into a single SQL script.