Relational database is a database that stores data in a tabular grid and uses features such as data integrity, normalization, query flexibility, data independence, scalability, concurrency, transactionality, and standardization A system for organizing data.
What is a relational database?
A relational database is a way of organizing data in which data is stored in a grid structure called a table. Each table contains a series of rows and columns, where each row represents an entity (such as a customer or product) and each column represents a specific attribute of the entity (such as a name or price).
Characteristics of relational databases:
1. Data integrity:
Relational databases use various constraints to ensure the accuracy of data and consistency, such as primary keys, foreign keys, and unique indexes.
2. Data normalization:
Data is organized into tables to eliminate redundancy and ensure the logical integrity of the data.
3. Query flexibility:
Relational databases provide powerful query languages (such as SQL) that allow users to efficiently retrieve and combine data from multiple tables.
4. Data independence:
The application layer and the physical data layer are independent of each other, allowing the database structure to be changed without affecting the application.
5. Scalability:
Relational databases can scale as data grows while maintaining high performance.
6. Concurrency:
Relational databases allow multiple users to access and modify data at the same time while maintaining data integrity.
7. Transaction:
Transactions provide atomicity, consistency, isolation and durability for a series of database operations, ensuring that data remains intact in the event of a failure.
8. Standardization:
The relational database model is defined by the ANSI SQL standard, making applications easily portable between different database systems.
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