Sitemap - 2025 - Alexander Obregon's Substack
Weekly Recap – June 15th, 2025
Build a Search Feature with SQL LIKE and Wildcards
Turning Rows Into Columns To Build Pivot Tables In SQL
Calculating Percent Change Between Rows in SQL
Breaking Big Queries into Manageable Parts with CTEs
Kotlin Enum Classes and the Companion JVM Code
LeetCode #11: Container With Most Water — Solved in Java
Working with JavaScript's PerformanceObserver to Track Web Vitals
How JavaScript String.raw Lets You Handle Escape Sequences Directly
LeetCode #10: Regular Expression Matching — Solved in Java
LeetCode #9: Palindrome Number — Solved in Java
What Happens When You Delete Properties in JavaScript Objects
Quick Update on the Java LeetCode Walkthroughs
LeetCode #8: String to Integer — Solved in Java
LeetCode #7: Reverse Integer — Solved in Java
LeetCode #6: Zigzag Conversion — Solved in Java
When Moving a Filter Broke My Join
Combining Tables With JOINs That Actually Match What You Want
Finding Missing Data Gaps in SQL Tables
Why JavaScript forEach Doesn't Wait for Promises
Reading Binary Data in JavaScript with Typed Arrays and ArrayBuffer
Grouping and Summing in One SQL Step for Clean Reports
Cleaning Up Dirty Data Using SQL
Finding Duplicate Records with SQL
Comparing Rows with SQL Window Functions
Writing SQL Queries That Run Faster
What I Posted This Week — JavaScript, Spring Boot, Java, Kotlin and Rewrites
Java Scope, Part 4 — try-with-resources and Catch Blocks
How JIT Compilation Uses Code Caching in Java
Every Bluetooth Update from 5.0 to 6.1 Explained
Class Unloading in Java and What Triggers It at Runtime
Where Synthetic Members Come From and Why the Compiler Creates Them
What I Posted This Week — JavaScript, Spring Boot, and Java
What Class Version Numbers Tell the JVM During Class Loading
Where Java Anonymous Classes Live in Memory and How They Behave
The Internal Steps of a ClassCast During Java Execution Test
What I Posted This Week — JavaScript, Spring Boot, and Java (Again)
LeetCode #5: Longest Palindromic Substring — Solved in Java
That One Lazy Bean I Didn’t Know About in Spring Boot
LeetCode #4: Median of Two Sorted Arrays — Solved in Java
LeetCode #3: Longest Substring Without Repeating Characters — Solved in Java
When @ComponentScan Skipped My Package
Java Scope, Part 3 — Loops, Lambdas, and Streams
What I Wrote This Week — JavaScript, Spring Boot, and Java
Execution Context and Call Stack in JavaScript
LeetCode #2: Add Two Numbers — Solved in Java
Java Scope, Part 2 — Methods, Fields, and this
LeetCode #1: Two Sum — Solved in Java
Java Scope, Part 1 — Local Blocks and Braces
Some Java Features That Come With Hidden Costs
How Java Actually Handles Exceptions Behind the Scenes
What I Wrote This Week — JavaScript, Spring Boot, and the JVM