Databases & Data

Where your data lives, and how to find it fast.

Series in this category

Complete courses on this topic, read in order. The standalone posts follow.

8 parts · ~50 min total · starts at Part 1

SQL Server → PostgreSQL

An eight-part translation guide for developers who know SQL Server and are moving to PostgreSQL — schemas, data types, T-SQL differences, PL/pgSQL, performance, backup and restore, and the migration itself. Current for PostgreSQL 18.

All 8 parts →🔧 T-SQL → PostgreSQL translator 🔧 Migration assessment report

7 parts · ~22 min total · starts at Part 1

Conversation to System Design

A seven-part, beginner-first series that takes one real conversation with a doctor and turns it into a complete database design — entities, attributes, relationships, keys and all.

All 7 parts →🗺️ System design hub

12 parts · ~74 min total · starts at Part 1

Database Design for Developers

Twelve hands-on parts from an ER sketch to a production schema, on SQL Server and PostgreSQL side by side: keys, relationships, column types, constraints, normalisation, naming, indexes, soft delete and history, migrations, and search. Every script was run on both engines; every output shown is real.

All 12 parts →📥 The finished clinic schema for PostgreSQL (every part has its own script to download)📥 The finished clinic schema for SQL Server 🧭 The series this one continues: Conversation to System Design 📦 ClinicLive, the clinic whose tables start the series

9 parts · ~63 min total · starts at Part 1

Student Projects: From Conversation to Database

Nine classic student projects, each designed from a conversation with the person who needs it: library, school, attendance, hostel, hospital, inventory, hotel, railway reservation and online shop. Entities, relationships, keys and CREATE TABLE scripts run on SQL Server and PostgreSQL, the viva questions answered with real output, the textbook mistake repaired, and an ER diagram for every one.

All 9 parts →🔧 Draw your own ER diagram from CREATE TABLE statements 🔧 Check a spreadsheet for normalization problems 🧭 The series this one follows: Conversation to System Design 🧭 The next step after a project: Database Design for Developers

Posts

Databases & Data

The dotnet ef Commands, Run and Explained: migrations, database and dbcontext

Every dotnet ef command run on a real solution. Target and startup project, add, list, script, remove, database update, dbcontext optimize and scaffold. Oct 14, 2026 6 min read

Databases & Data

PostgreSQL vs SQL Server for .NET Developers: The Real Differences

PostgreSQL vs SQL Server, decided by someone who ran both. Licensing, EF Core support, tooling, hosting, JSON, full-text search, and what hurts in a migration. Sep 4, 2026 9 min read

Databases & Data

PostgreSQL 16 vs 18 for .NET Developers: Run Side by Side

PostgreSQL 16 vs 18, run side by side. uuidv7, virtual generated columns, RETURNING OLD and NEW, temporal keys, skip scans, and how to move a dev database. Oct 14, 2026 6 min read

Databases & Data

SQL vs NoSQL: Which Database Should You Learn First?

Tables or documents? Rows or JSON? What each kind of database is good at, where each struggles, and a clear recommendation for your first one. Jul 30, 2026 5 min read

Databases & Data

What Is a Vector Database? (And Why AI Needs One)

Vector databases search by meaning, not keywords. How embeddings turn text into numbers, and how similarity search powers RAG and semantic search. Jul 30, 2026 4 min read

Databases & Data

Database Indexes: Why Your Queries Are Slow

Scan a million rows, or jump straight to one. How indexes work, when to add them, and the trade-offs nobody mentions. Jul 30, 2026 5 min read

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