Browsing Tag
sql
109 posts
I built a free SQL practice game where you work at a fictional Singapore bank
I’ve been frustrated with SQL learning resources for a while. Most are either: Dry reference docs Toy exercises…
Debugging PostgreSQL Performance
Let’s chat about performance, optimization, and debugging a PostgreSQL database. Can you read EXPLAIN ANALYZE output fluently? Do…
Stop Naming Your Healthcare Columns Wrong — ISO-11179 Explained
If you’ve ever inherited a healthcare database with columns named DOB, PatientID, or CLAIM_NUMBER — this guide is…
SQL Subquery and CTEs( Common Table Expressions)
What is a subquery? Subquery is a query nested inside another query statement. It allows the query to…
Coding Cat Oran Ep3, Five Tables Changed Everything
Oran spent two weeks doing something that felt like not working. He sat with the warehouse team during…
From Scratch to Queries: Building a School Database with SQL – My Nairobi Academy Project.
Transitioning from viewing data as simple lists to managing it within a relational database is a milestone for…
How I Learned SQL by Creating a Simple School Database
Introduction When I first started learning data analytics, I spent most of my time working with tools like…
Azure SQL Database: Cross-Database Queries on the Same Server
If you have two databases on the same Azure SQL logical server and try a three-part name query…
Alter Queries
In this assignment, I worked on modifying existing tables using ALTER TABLE. This helped me understand how to…
PostgreSQL(Alternations)
-ALTER TABLE → modify existing table structure. -Operations: add/drop column, change datatype, rename column/table, add/drop constraints. Common ALTER…
