AAbolfazl Mohajeri10h ago · 14 min readHow Does PostgreSQL Decide How to Execute a Query?When you send a SQL query to a database, have you ever wondered what actually happens behind the scenes? Consider the following query: SELECT * FROM orders WHERE user_id = 123 ORDER BY created_at DESCblog.abolfazlmohajeri.ir
Jjaberadam200113h ago · 11 min readMoney Rounding Errors: Allocate the Remainder, Don't DivideHere's a query worth running against your production database this week: -- Orders whose installments no longer add up to the order total SELECT o.id, o.total_minor, SUM(i.amount_minor) AS installmentsimplyexplained.hashnode.dev
DDave Kurian15h ago · 8 min readHow to choose a SaaS boilerplate you can reuse for your next productA SaaS boilerplate is worth buying when it removes work you would otherwise have to build, while leaving the important decisions understandable and changeable. A long feature list cannot tell you thatotf-kit.hashnode.dev
GGowtham Muthuvel22h ago · 17 min readIdempotency Keys in Spring Boot: Making POST Safe to RetryI fired the same POST /orders request 20 times at the same instant, with the same Idempotency-Key header, at three versions of one Spring Boot endpoint. Here is what landed in the database: /v1/ordersgowthammuthuvel.hashnode.dev
DDave Kurian18h ago · 8 min readHow to test two-account data isolation before sharing an AI-built SaaSThe login page works. That still does not tell you whether one account can read another account’s records. Before sharing an AI-built app, test the boundary with two accounts and data you created for otf-kit.hashnode.dev
NNibbo18h ago · 3 min readYour Upload Form Is Publishing Users' Home Addresses: Stripping EXIF Client-Side and Server-SideIf your app lets users upload photos (marketplace listings, avatars, support tickets, community posts) and you serve the original file back, there's a good chance you're also serving the GPS coordinatnibbo.hashnode.dev
YYash Dhawane1d ago · 6 min readScalability: Why Adding More Servers Isn't Always the AnswerI'm learning High-Level Design (HLD), and one of my first lessons was about scalability. Before this, when I thought about a system struggling with increasing traffic, my instinct was simple: add moreyashdhawane.hashnode.dev
GGowtham Muthuvel1d ago · 18 min readReplacing ThreadLocal with ScopedValue for Request IDs (Java 25)Here's a log line from the demo in this post. Request #3 came in without an X-Request-Id header, yet it was logged with the ID of a different request: http-nio-1 requestId=req-A handling requesgowthammuthuvel.hashnode.dev
UUsman Khan1d ago · 8 min readForeign Key Cascade Deletes: Un-Indexed FKs, Slow Cascades, and Lock Contention in PostgreSQLRunning a DELETE on a parent entity with ON DELETE CASCADE feels like clean relational cleanup. But if any child or grandchild table in the dependency chain lacks an index on its foreign key column, P12MActousman.hashnode.dev
VVortex Web Innovate1d ago · 1 min readWhat Is API Integration? API vs Integration, ExplainedAn API is the interface a system exposes. An API integration is the logic that uses those interfaces for a business purpose, including what happens when something fails. This guide explains the differvortexwebinnovatehq.hashnode.dev
