Learn SQL and Databases the Easy Way
Plain-English guides to SQL, database design and big data, written by a developer who works with databases every day. No jargon, lots of real examples.
Where Do You Want to Start?
New to SQL
Write your first queries and learn to filter, sort and summarise data.
Designing a Database
Build tables that keep your data clean, consistent and easy to query.
Going Further
Speed up queries, protect your data and write smarter SQL.
Latest Articles
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Learn data cleaning in SQL step by step: trim spaces, turn blanks into NULL, fix text numbers and mixed date formats, and remove duplicates, with SQL Server and MySQL examples. - SQL Server Blocking: How to Find the Blocking Session (and Fix It)
How to find blocking in SQL Server in under a minute: the DMV queries that show who is waiting and who the head blocker is, what to do right now, and how to stop blocking from coming back. - Why Delphi Is Still a Great Choice for ERP and Business Apps in 2026
Why Delphi is still a strong choice for ERP and business software: visual forms, built-in database access, native speed, a long life, and the honest downsides. - Delphi Basics: Variables, Data Types, If, Case and Loops Explained Simply
Learn Object Pascal basics in Delphi: variables, constants, data types, strings, if/else, case and for, while and repeat loops, with runnable examples. - ETL vs ELT Explained Simply (With a SQL Transform Example)
What ETL and ELT mean, how they differ, what the transform step looks like in real SQL, full vs incremental loads, and which approach to choose for your data warehouse. - Star Schema vs Snowflake Schema: Fact and Dimension Tables Explained
What a star schema is, how fact and dimension tables work, how to query them with plain SQL, how the snowflake schema differs, and which one to choose for your data warehouse. - OLTP vs OLAP Explained Simply (With SQL Examples)
What OLTP and OLAP mean, how they differ, why heavy reports slow down a live database, and how data moves from one to the other, explained in plain English with SQL examples. - 25 SQL Interview Questions for Beginners (With Answers)
25 SQL interview questions that come up again and again for junior roles, with short answers you can say out loud: joins, GROUP BY, NULL, keys, indexes, ACID, and three classic write-a-query tasks. - What Is Delphi? Install Delphi Community Edition and Build Your First App
A beginner’s guide to Delphi: what it is, what it’s used for, how to install the free Community Edition, and how to build your first Windows app step by step.