The database describes the specific methods for organizing, managing and updating the data. If you’re looking to start a career in this industry, it is important that you cover both the major and minor areas. The current job market is very competitive. Everyone wants to be in a good job.
To help you on your journey to a database role, here are some tips. This blog will discuss and teach you the most important database questions. These questions will give you confidence and cover all the important concepts of the data base. So, let’s begin!
Top Database Interview Questions
1. Define database.
A database is a managed collection of data that can be used to store, access, and organize data for specific purposes. This allows you to organize data into tables, rows and columns, and index it to make it easy to find the relevant information. For example, a chemist must keep track of all medicines in the medical shop.
2. What is DBMS?
DBMS stands for Database Management System. This is a group of applications that allow users to organize, restore, and retrieve data efficiently and effectively. MySQL is one example.
3. What is RDBMS?
RDBS stands to Relational Database Management System. It is based on a relational data model. RDBMS’ main purpose is to store data in separate tables. They are linked by the use of a common row. Structured Query Language (SQL) allows data to be accessed from relational databases.
4. Can you list some of the benefits of a Database Management System, (DBMS)?
These are the benefits:
DBMS is structured data storage that manages data redundancy.
Second, only authorized users have access to the database. They must have a username, password, and access to the database.
It also provides data integrity, which allows you to verify data consistency and accuracy.
The next step is to support backup and recovery of data when needed.
It also offers multiple user interfaces.
5. Explain Data Redundancy.
Data redundancy is the duplication or multiple copies of the same data. This duplicate data can also be found in multiple databases, which can cause storage space wastage and even compromise data integrity.
6. What are the different types of relationships in the Database?
There are three types:
1. One-to-one
This is when a table has a relationship to another table with the same column. This means that every primary key is only applicable to the record in the related table.
2. One-to-many
This is when a table has a relationship to another table that contains primary and foreign key relationships. The primary key table is composed of one record that is related to none, one, or more records in the related tables.
3. Many-to-many
This is when each record in one table can be referred to as many records in the other.
7. Define Normalization.
Normalization is the process of removing redundant data from a database. This is done by splitting the table in a understandable way to maintain data integrity. This process can be used to manage and save storage space.
8. What is De-normalization?
De-normalization is the process of adding redundant copies of data to the table in order to increase the speed of complex queries and improve performance.
9. Name the different types of Normalization.
1. 1NF
A relation is First Normal Form (1NF), which means that all entities in the table have unique or atomic values.
2. 2NF
A relation is Second Normal Form (2NF), if it is in 1NF. All the non-key at