Characteristics of relational databases

Features of relational databases include: table structuring; relationship establishment; data integrity constraints (primary key, foreign key, non-null); transaction support; data manipulation language (DML); data query language (DQL); and data security measures.

Characteristics of relational database

Relational database is a database that organizes and stores data in the form of data tables management system. It has the following main features:

1. Table structure:
Data in a relational database is stored in a relational structure called a table. A table consists of rows and columns, where rows represent individuals of entities and columns represent attributes of those entities.

2. Relationship:
The relationship between tables is established through foreign keys. A foreign key is a column or set of columns that references a primary key in another table, indicating a relationship between the two tables. This allows connections to be made between different tables.

3. Data integrity:
Relational databases ensure data integrity through constraints, which specify the rules that the data must follow. Common constraints include:

• Primary key constraints: Ensure that a row in each table is identified by a unique identifier (primary key).
• Foreign key constraints: Ensure that the foreign key column refers to rows that exist in the main table.
• Non-null constraint: Ensure that null values ​​are not allowed in the column.

4. Transaction support:
Relational databases ensure data consistency through transaction support. A transaction is a sequence of operations that either all succeed or all fail. This prevents incomplete or inconsistent data updates.

5. Data Manipulation Language (DML):
Relational databases use DML (such as SQL) to perform data manipulation operations. DML commands allow users to create tables, insert, update, and delete data.

6. Data Query Language (DQL):
Relational databases use DQL (such as SQL) to retrieve data. DQL commands allow users to query data using advanced conditions and produce the desired results.

7. Data security:
Relational database supports data security measures, such as:

• Access control: restrict user access to data.
• Authentication: Verify user identity.
• Encryption: Protect sensitive data from unauthorized access.

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