List of Lessons | Subjects

Understanding SQL

by Ron Kurtus (updated 17 March 2023)

SQL (Structured Query Language) is a computer language used to query or make commands to a database. It is structured to be relatively straightforward and simple to use. SQL is used with such databases as Microsoft Access, My SQL, and Microsoft SQL Server. It is often used with Web programming languages, such as ColdFusion, ASP, and PHP.

The purpose of these lessons is to provide you with the basics of using SQL to query a database. It is also useful for those studying Web programming and e-commerce.

SQL Contents


Database Basics

Retrieving Columns of Data

Sorting Retrieved Column Data

Filtering Data Retrieved from a Database Table

Advanced Data Filtering (coming soon)

Wildcard Filtering

Creating Calculated Fields

Data Manipulation Functions

Summarizing Data

Grouping Data


Joining Tables

Advanced Joins

Combining Queries

Inserting Data

Updating Data in SQL

Deleting Data

Creating Tables

Manipulating Tables


Transaction Processing


SQL Resources

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