SQL (Structured Query Language) is the standard language for interacting with relational databases. It allows defining schemas, querying data, and managing database structures in a predictable, table-based format.
Characteristics
- Structured, relational model: Data is stored in tables with rows and columns.
- Schemas: Enforces strict rules for data integrity and relationships.
- ACID Transactions: Ensures reliability with atomicity, consistency, isolation, and durability.
- Joins: Allows combining data across related tables.
Advantages
- Strong data integrity and reliability.
- Powerful querying with joins, filtering, and aggregations.
- Mature ecosystem and widespread support across industries.
- Ideal for structured, consistent data models.
Limitations
- Less flexible for unstructured or rapidly changing data.
- Scaling horizontally can be complex compared to NoSQL.
- Requires predefined schema before storing data.
Purpose
SQL databases are best suited for structured data and transactional applications, such as banking systems, e-commerce platforms, and enterprise software. They are a core pillar of Web Development alongside NoSQL for modern database architectures.