A Node process, a file named mydb.db, and the sqlite3 binding are enough to keep a local table without a server. Most copy-pasted snippets hide how serialize and close ordering decide whether you see rows at all, which means you…
Opening a new MySQL connection per request exhausts the connection limit under concurrent load. A pool keeps a small set of connections alive and reuses them across requests. This guide builds a mysql2 pool with createPool, runs queries against it,…
Sequelize 6.37.8 with pg 8.23.0 on Node v26.7.0 gave me a clean connection. This refresh replaces the 2017 install steps with a run I actually executed against PostgreSQL 18.6. I installed sequelize, pg and pg-hstore in a fresh folder, then…
I wrote this limiter twice in one sitting. The version I started with counted calls with a read followed by a write, which is the shape the shorter walkthroughs on this query still use, and twenty concurrent calls against a…
When you build an offline-first app, the question is what happens to a change while there is no network. The answer is a queue that writes to IndexedDB first, pushes to MySQL, and clears the local copy only after the…
Adding live search to a Node.js and MySQL app takes a query, an endpoint, and a little front-end code. The last step is a search box that filters the table as you type. Express 5.2.1, mysql2 3.24.4 and MariaDB 10.11…
A polling page becomes live when a vote reaches RethinkDB, the database emits the changed document, and a Node.js server forwards that event to connected browsers. This refresh builds that path with Express, the RethinkDB JavaScript driver, and Socket.IO, then…
IndexedDB lets your JavaScript application store structured data in a browser, then query that data without sending every read to a server. I checked the current browser API guidance from MDN, web.dev, and the Indexed Database specification, then ran the…
An Express session has two halves: a signed identifier in the browser and server-side data attached to that identifier. Redis gives every Node.js process the same place to find that data, with an expiry timer on each session key. I…
Post a comment in one browser and watch it appear in a second browser in the same second, with a desktop notification on top. That is the whole project. You build it with Express, a MySQL database, and Socket.IO broadcast,…
