Shared from "Study" on Inkdown
At its core, a database is an organized collection of data that can be easily accessed, managed, and updated. Think of it as a digital filing system that's smarter, faster, and more reliable than storing data in files.
A DBMS is software that interacts with end-users, applications, and the database itself to capture and analyze data. It provides:
The heart of the database - decides HOW data is stored and retrieved.
B-Tree Engine (InnoDB, PostgreSQL)
LSM-Tree Engine (Cassandra, RocksDB)
Ensures data integrity when multiple operations happen together.
| Term | Definition | Analogy |
|---|---|---|
| Schema | Structure/blueprint of database | House floor plan |
| Table/Collection | Group of related data | Excel sheet |
| Row/Document | Single record | One row in Excel |
| Column/Field | Attribute of data | Column in Excel |
| Index | Data structure for fast lookup | Book index |
| Primary Key | Unique identifier for each row | Social Security Number |
| Foreign Key | Reference to another table's PK | Pointer to related data |
| Query | Request for data | Asking a question |
| Transaction | Group of operations treated as one | Bank transfer (debit + credit) |
Now let's dive deeper into each topic: