SQL Tutorials – Learn SQL from Basics to Advanced

SQL is the standard language for working with relational databases. These guides cover querying, managing databases and tables, modifying data, and keeping your database secure and performant. Whether you're writing your first SELECT or optimizing slow queries, you'll find a practical guide for it here.


Getting Started

The essentials before anything else: how to run queries, how to write them well, and how to document your SQL code with comments.


Databases

Everything related to creating and managing the database itself, including backups before you make changes you might regret.


Tables

Tables are where your data lives. These guides cover the full lifecycle: creating, copying, renaming, clearing, and dropping them.


Columns & Data

Adding and changing what's inside your tables — columns, rows, and the data stored in them.


Querying Data

The core SELECT toolkit. These guides cover filtering, sorting, deduplicating, and limiting results — everything you need to retrieve exactly the data you're looking for.


Joins

Joins combine data from multiple tables. These guides cover each join type and explain when to use one over another.


Aggregation & Grouping

Summarizing data across rows — counts, sums, averages, and grouping results with filtering on the aggregated output.


String & Date Functions

Built-in functions for transforming text and working with date values inside your queries.


Advanced Queries

Beyond basic SELECT: combining result sets, conditional logic, nested queries, deduplication, and pivoting data.


Schema & Constraints

The structural rules that keep your data consistent and your queries fast — keys, indexes, auto-increment, and data types.


Programmability

Reusable database objects — views, stored procedures, functions, triggers, and transactions — that move logic closer to the data.


Import & Export

Moving data in and out of your database — useful for migrations, backups, and working with external data sources.