Database Management System - DBMS Tutorial
In the modern era, businesses and organizations heavily rely on data. To manage large amounts of data effectively, they need tools and systems that can store and manipulate it. This is where Database Management Systems (DBMS) come in. Our tutorial covers basic to advance topics and concepts related to database.
What is Database?
A database is a collection of organized and structured data that can be accessed, managed, and updated easily. It is designed to efficiently store and manage large amounts of data, which can be anything from text, numbers, images, or multimedia files.We also can use it to organize table ,records ,schema ,reports etc .The main purpose of using database is to efficiently handle vast amounts of information by storing, retrieving, and managing data.
Some of the databases used commonly are MySQL ,Oracle, MongoDB ,Sybase ,PostgreSQL etc.Most of the modern databases are managed by Database Management System.
Database Management System
A Database Management System (DBMS) is a software that enables us to create, store, modify, and retrieve data from a database.
The database management system (DBMS) is responsible for managing modern databases, which commonly include MySQL, Oracle, MongoDB, Sybase, PostgreSQL, and others.
Characteristics of DBMS
- Security and redundancy: DBMS provides security features to prevent unauthorized access to the data and removes redundancy to ensure data consistency and accuracy.
- Backup and Recovery:The backup and recovery feature of DBMS is used to ensure data safety and continuity by creating backups and restoring them in case of system failures.
- Data modeling:DBMS helps in creating and modifying different datamodels ,that defines the structure of data in databases.
- Multiuser / Concurrent Access :It allows multiple user to access and also manipulate data in database concurrently .But there lies some restriction on attempt to handel same data at same time.
- ACID compliance: Dbms follows the concepts Atomicity, Consistency, Isolation, and Durability (ACID) to maintain the health of the database in multi-transactional environments and in case of failure.
- Relational-based table : DBMS enables the formation of tables by representing entities and their relationships in a relational-based structure.
- Data storage and retrieval: DBMS has the primary responsibility of storing and retrieving data from the database, and offers a range of methods that allow users to search and query the stored data in various ways.
- Normalization: DBMS follows normalization rules to minimize data redundancy and ensure consistency in every relation within the database
- Query language: DBMS is equipped with a query language that facilitates efficient data retrieval and manipulation.
Advantages Of DBMS
Here are the advantages of DBMS :
Reducing Data Redundancy: By storing data in a central database, DBMS avoids duplication of data and ensures that any change in the data is reflected immediately, which prevents the possibility of encountering duplicate data.
Data Sharing: DBMS allows multiple users to access and share data based on authorization protocols, enabling remote users to simultaneously access and share data among themselves.
Data Integrity: Ensuring accuracy and consistency of data across multiple databases is crucial in a DBMS to maintain the integrity of data visible to multiple users.
Data Security: DBMS protects the database from unauthorized access by allowing only authorized users to access the database, and their identity is authenticated using a username and password.
Privacy: DBMS restricts access to authorized users based on privacy constraints, ensuring that only those with proper authorization can view specific data.
Backup: DBMS automatically takes care of backup and recovery, eliminating the need for users to perform periodic backups, and restoring the database to its previous state after a system failure.
Data Consistency: In a DBMS, data consistency is ensured by eliminating data redundancy and displaying data consistently across the database, with any changes made immediately reflected to all users, preventing data inconsistency.
Disadvantages of DBMS
Some of the disadvantages of dbms are:
Complexity: DBMS is a complex software system that requires specialized technical knowledge to set up, operate and maintain, making it challenging for non-technical users.
Cost: Implementing and maintaining a DBMS can be expensive, including the cost of acquiring hardware, software, licenses, and hiring skilled personnel.
Database crashes: Although DBMS provides automatic backup and recovery, database crashes can still occur, causing data loss or corruption, which can be challenging to recover.
Performance: When compared to file-based systems, DBMS can have a slower performance due to its additional processing overhead, especially when the number of users accessing the database is high.
Security vulnerabilities: Despite the security measures in place, DBMS can still be vulnerable to external attacks or unauthorized access, which can compromise sensitive data.
Data inconsistency: DBMS requires careful planning and design to avoid data inconsistencies and redundancy, which can be challenging to manage, especially in large or complex databases.
Dependence on DBMS vendors: Organizations using DBMS are dependent on the vendor for support, upgrades, and fixes, making it challenging to switch to a different system, especially if the vendor goes out of business or stops supporting the product.