List of free SQL stuff for developerππ½
If you're looking for all programming tools around SQL (not just free). Check this page List of SQL Programming Tools
Directus
Open-Source Data Platform β Directus wraps any SQL database with a real-time GraphQL+REST API and an intuitive app for non-technical users. 100% JavaScript.
Tag: Database, SQL, GraphQL, API, CMS
Completely Free and Open-Source Works with any New or Existing SQL Database REST & GraphQL API Powerful Content/Data/Asset Management Completely Flexible Content Structure

SQLite Viewer Web App
A free online SQLite Explorer, inspired by DB Browser for SQLite and Airtable. Use this web-based SQLite Tool to quickly and easily inspect sqlite files on the web.
Tag: sql, playground

Sequel Ace
Sequel Ace is a fast, easy-to-use Mac database management application for working with MySQL & MariaDB databases.
Tag: sql, database
Mac OS X only
HeidiSQL - MariaDB, MySQL, MSSQL, PostgreSQL and SQLite made easy
HeidiSQL is a free and powerful client for MariaDB, MySQL, Microsoft SQL Server, PostgreSQL and SQLite
Tag: database-gui, sql, nosql
Open Source Only for Windows

Flatbase
Query your CSV and JSON files with SQL. Flatbase is the data science platform for developers. Upload files, write SQL, visualize results, and share with collaborators.
Tag: sql, json, api, playground
Up to 3 workspaces Share with up to 3 teammates

Format Express
Instant online formatter for JSON / XML / SQL : what you paste is immediately beautified with syntax highlighting, node navigation, minimap, search tools, ...
Tag: json, xml, sql, formatter
Illimited use. No ads, no tracking.
Dolt | Git for Data
Dolt β It's Git for Data. Contribute to dolthub/dolt development by creating an account on GitHub.
Tag: sql, git, version, data
Is a open source project only (for now) MySQL support