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Beginner 1 minute
SQL Databases
SQL databases organize data into tables, rows, and columns with a defined schema. Relationships and constraints help keep records consistent, while SQL lets you filter, join, aggregate, and update data precisely. They are a strong default for transactional systems where correctness matters, especially when several changes must succeed or fail together.
Key idea
Tables plus relationships plus transactions make structured business data dependable.
See it in one picture
Follow the arrowsOrders
Customers
Products
Relations
Related records stay organized
Real-world example
An order system can store customers, orders, and line items in related tables. A transaction can create an order and reserve inventory together, preventing half-finished purchases.
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