02 - Relational vs NoSQL Database (Video in Khmer)
Learn the difference between relational and NoSQL databases with clear examples, practical tips, and videos in Khmer.
2026-08-22 · 3 min read
Hello my friend! In this lesson, we compare relational databases and NoSQL databases. We look at how they store information and when each type can be useful. The videos are in Khmer.
What is a relational database?
A relational database stores information in tables. Each table has rows and columns. Tables can connect with each other using keys.
For example, a school database can have a students table and a classes table. A student record can connect to a class record with an ID.
Relational databases usually use SQL to create tables, add data, and find information. MySQL, PostgreSQL, and Microsoft SQL Server are examples.
Watch the video:
What is a NoSQL database?
NoSQL databases store information in ways that are not only tables. Some store documents, key-value pairs, or connected data. The exact format depends on the database.
Some NoSQL databases let documents have different fields. This can be useful when the information changes often. MongoDB is one example of a document database.
Watch the video:
Main differences
| Relational database | NoSQL database |
|---|---|
| Stores data in tables with rows and columns. | Can store data as documents, key-value pairs, or other formats. |
| Tables can connect using keys. | Data structure and relationships depend on the database type. |
| Often a good fit for structured data and complex table queries. | Can be a good fit for flexible data or document-style access. |
| Examples: MySQL, PostgreSQL, and SQL Server. | Example: MongoDB (document database). |
Both types can work well. The right choice depends on your data, application, and how you need to use the data.
Tips
- Write down the kind of information your application needs to store.
- Choose a relational database when data has clear structure and needs links between tables.
- Consider NoSQL when a document-style or flexible data structure fits your application.
- Check how you will search and update data before choosing a database.
- Try a small sample project first. Do not choose only because a database is popular.