Please answer the question attached.. it is of computer subject. chapter name is open office base....
Answers
Jack has created a table for his book store. The table includes book còde, book name, book publisher and book cost. Which field will he select for creating the primary key?
Answer:
Book Còde
The book còde must be selected as the primary key in the table. The book còde is a unique value and helps us to obtain the complete information regarding the book of which the còde belongs. That is, by using book còde as the primary key, we can get the name of the book, book publisher and other details.
Extra information:
Primary Key
A primary key is the unique column name present in a table of data that helps us to identify a set of data. It does not have a variable value. A table has only one primary key. For example, Admission number in a student list can be considered as a primary key.
Alternate Key
A unique column name that also has the capability of being a primary key. (But it has not been selected as a primary key.) For example, in a class list, the roll number column is the primary key and the admission number column is the alternate key.
Candidate Keys
The primary key and alternate keys together for the candidate keys. All of them are fit to be a primary key.