What problems do relational databases solve?

Relational databases solve several key problems related to data storage, management, and retrieval. They provide a structured way to store data in tables with predefined schemas, ensuring data integrity, consistency, and efficient querying. Here’s a breakdown of the problems they address, along with examples:

Data Organization and Structure
Relational databases organize data into tables (relations) with rows (records) and columns (fields), making it easy to store and manage structured data. For example, a customer table might have columns like CustomerID, Name, and Email, with each row representing a unique customer.
Data Integrity and Consistency
They enforce constraints (e.g., primary keys, foreign keys, unique constraints) to ensure data accuracy. For instance, a primary key ensures no duplicate records, while foreign keys maintain relationships between tables (e.g., linking an Order table to a Customer table).
Efficient Data Retrieval
Relational databases use SQL (Structured Query Language) for powerful and standardized querying. Complex queries (e.g., filtering, sorting, joining multiple tables) can be executed efficiently. Example:
```
SELECT Orders.OrderID, Customers.Name 
FROM Orders 
JOIN Customers ON Orders.CustomerID = Customers.CustomerID 
WHERE Orders.Date > '2023-01-01';
```
ACID Transactions
They support ACID (Atomicity, Consistency, Isolation, Durability) properties, ensuring reliable transactions. For example, in a banking system, transferring money between accounts requires all steps (debiting one account and crediting another) to succeed or fail together.
Scalability for Structured Data
While not inherently designed for unlimited horizontal scaling (unlike NoSQL), relational databases can scale vertically (better hardware) and handle large datasets efficiently. For high-performance needs, managed relational database services like TencentDB for MySQL/PostgreSQL offer optimized performance, backups, and auto-scaling.

Example Use Cases:

E-commerce: Storing product catalogs, orders, and user profiles with relationships.
Banking: Managing transactions, accounts, and customer data with strict integrity.
Enterprise Systems: HR databases for employee records, payroll, and department structures.

For scalable and managed relational database solutions, Tencent Cloud’s TencentDB provides high availability, automated backups, and security features tailored for business needs.