NocoDB
A self-hosted Airtable alternative that presents PostgreSQL and MySQL databases as spreadsheets. Runs on your server with Docker; hosted service available.
Alternative to:

NocoDB is a self-hosted database workspace for teams that want to manage records through a spreadsheet interface. It runs on your own server with Docker and can connect to existing PostgreSQL or MySQL databases. A hosted service is also available.
Teams can use it for customer records, project tracking or inventory without writing database code. Grid views support sorting, filtering and grouping; Kanban and gallery views present the same records in other layouts. Forms collect entries, and calendar views show records with dates.
Linked records, lookups and rollups connect information across tables. Formula fields and attachments support calculations and files alongside those records. You can edit multiple fields together and inspect table relationships in an ERD diagram.
Role-based access controls govern who can work with the data. Teams can share bases or views publicly or privately, protect shared access with passwords, and use locked views where they need a fixed presentation.
NocoDB imports data from Airtable, CSV and Excel. REST APIs, its SDK and webhooks connect the workspace to other software; workflow integrations include Slack and Mattermost for messaging, SMTP for email, and AWS S3 or Minio for storage.
NocoDB follows a fair-source model under the Sustainable Use License. Its browser interface also supports viewing and editing records from a smartphone.