Because of such potential pitfalls, a frequently used option is to create a unique candidate key. In this case, the bank’s database can issue unique account numbers that are guaranteed to prevent the problem just highlighted. For good measure, these account numbers can have some built-in log...
{Roll_no, Registration_no}:This key cannot be considered as a candidate key because when we take the subset of this key we get two attributes i.e Roll_no or Registration_no. Each of these attributes is the candidate key. So, it is not a minimal super key. Hence, this key is not ...
even if they execute concurrently. Transactions that are not serializable may produce incorrect results. There are different types of serializability in DBMS with different advantages and disadvantages. Here, we'll look closely at two of the most common types: conflict...
In summary, a good primary key is one that is unique, stable, simple, and ideally sequential and minimal in size. On the other hand, primary keys that are non-unique, complex, mutable, large, or carry meaningful and sensitive information, are generally not advisable. The choice of a prima...
A database table must have a primary key and may also have foreign keys. When a database is normalized the data will appear only once in one table and will not be duplicated in another table.Answer and Explanation: Become a member and unlock a...
Another is “S 201003 004” for the fourth savings account created in March 2010. This is a composite key, that is, a candidate key that guarantees uniqueness only when two or more columns are joined together. A composite key can be defined as the primary key. This is done using SQL ...
What key roles should a data management team include? Storage engine.This basic element of a DBMS is used to store data. The DBMS must interface with a file system at the operating system (OS) level to store data. It can use additional components to store data or interface with the actua...
Some of the fields where a database management system is used given below: HR Management: Employees’ information and salary-related activities can be managed in DBMS software. Banking:Customer records, customer information, account activities, payments, deposits, loans can be managed by DBMS softwar...
DBMS | PJNF (Project-Join Normal Form): In this tutorial, we will learn about the PJNF (Project-Join Normal Form), Properties of 5NF with the help of examples.ByIncludeHelpLast updated : May 29, 2023 Overview Database normalizationis the method of restructuring a relational database in ...
What is the primary purpose of a data warehouse? A combination of several columns that together serve as the primary key is called what? (a) foreign key (b) composite key (c) candidate key. What is the primary objective of data security controls?