Observable - Interactive code examples/posts
DBeaver - DBeaver - Universal Database Manager and SQL Client.
nbviewer.org - Rackspace server host Jupyter Notebooks from your github repo
DataGrip - Tool for SQL and databases
Jupyter - Project Jupyter exists to develop open-source software, open-standards, and services for interactive computing across dozens of programming languages. Ready to get started? Try it in your browser Install the Notebook.
HeidiSQL - HeidiSQL is a powerful and easy client for MySQL, MariaDB, Microsoft SQL Server and PostgreSQL. Open source and entirely free to use.