Redash is a web console for interfacing with databases, building queries and reports, and visualizing results. Includes SQLite, MySQL, Postgres, and even JSON documents. Snippets can be saved. Caches results, can autoupdate. Can join across different databases. Dashboards can be shared via unique links. Of course, has an API.
Github repo: https://github.com/getredash/redash
There is also an Electron webshit version for download.
Online version, free to use: https://app.diagrams.net/
A chart and diagram webapp written in HTML5 that lets you do pretty much whatever Lucidchart does. Export to PNG, GIF, and JPEG.
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